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Social, spatial and political determinants of U.S. abortion rates
0277-9536/82/090987-10503.00/0 Copyright 0 1982 Pergamon Press Lrd
Sot. &I. Med. Vol. 16. pp. 987 IO 996. 1982 Pruned in Great Britain.All rights reserved
SOCIAL, SPATIAL AND POLITICAL DETERMINANTS U.S. ABORTION RATES
OF
NORAH F. HENRY’ and MILTON E. HARVEY’ ’ Department of Geography, State University of New York at Binghamton, NY 13901 and
‘Department
of Geography. Kent State University, Kent, OH 44242. U.S.A.
Abstract-Abortion rates in the United States have risen annually since the 1973 Supreme Court decision. The regions with the greatest rate increases are the Southern and Plains states; the lowest rate increases were in regions which had high abortion rates soon after abortion was legalized. While spatial contiguity appears to influence abortion rates. that is. states with high rates of abortion are clustered spatially. social and political influence are also evident. Ratification of the equal rights amendment. the seeking of abortion outside the state of residence, and the degree of urbanization within a state are variables which influenced U.S. abortion rates between 1973 and 1977.
INTRODUCTION
In the 1960s increased social consciousness, advances in medical technology, and third party payment programs increased the technical quality of health care and the numbers and groups of persons to whom services were provided. One group to benefit from the increased attention was women. Advances in medical technology provided safer. more effective modes of birth control. Sophisticated monitoring devices could be employed to detect in utero fetal distress and pregnancy termination procedures were developed which mitigated previous difficulties in abortion. Of these medical services abortion has attracted considerable attention. The number of abortions performed in the United States has increased dramatically since the 1960s. Most of the increase occurred following the 1973 Court decision. However, despite the legality of abortion. differences in abortion rates persisted through the 1970s. The purpose of this paper is to investigate the spatial diversity in abortion rates in the United States between 1973 and 1977. Understanding the diversity present in the rates of abortion involves examination of political, social, economic. and spatial constraints. A comprehensive treatment of their collective impact upon abortion rates is lacking. despite the range of topics included in abortion studies. This paper (a) examines the changes in abortion rates in the coterminous United States, and (b) assesses the relative importance of spatial, political and social determinants in the distribution of abortion rates. ISSUES IN ABORTION
Spatial components of abortion have been examined by both geographers and non geographers. The findings of this research, detailed below, .indicate clearly a spatial bias in abortion-facility location and in abortion accessibility. Spatial dimensions
Spatial components of abortion which have been investigated include: (1) the relationship between metropolitanism, abortion rates and locations of abortionists; (2) locational inequities: (3) the process by which facilities spread; and (4) patient travel behavior. A high metropolitan concentration of abortion facilities exists, with west coast and northeastern urban centers displaying the greatest concentrations [l, 2). Abortion clinics provide more abortions than do other types of facilities (i.e. hospital, private physicians), and are generally found within urban areas. The increase in the number of clinics has been related to the increase in abortion rates in the ten SMSAs with the largest increases in abortion rates [3]. The metropolitan aspect is only one issue in abortion facility location and abortion accessibility. Location of abortion facilities in the United States generally has followed the urban hierarchy. In larger urban areas abortion facilities were established shortly after abortion was legalized. Establishment of these early facilities was followed by (1) an increase in number of facilities at the initial locations. and (2) the location of new facilities in smaller urban centers [2]. However, spatially abortion services are not uniformly available in urban areas, nor equally accessible within states. While ail states have at least one facility which will provide pregnancy termination at the request of the woman. there is considerable variation in the. number of providers and the number provided for. In 1977, for example. 2387 (77”/;,of all U.S.) counties had no,abortionist identified with them Cl]. The inability to secure an abortion easily in her home area may lead a woman to travel to a different locale where abortion is more readily available. In 1977 approx. 9“, of all U.S. abortions were performed outside the state of residence. While this represents a substantial decrease from 25.2O,,in 1973 and 43.8:” in 1972. it continues to illustrate a shortage of abortion
STUDIES
Abortion has received a tremendous amount of attention in the literature and has been the procedure on which the greatest amount has been published. Topically. the scope of abortion studies has been wide. Analysis of the demographic characteristics of abortion patients. abortion-rate differentials. the availability of abortion to women desiring pregnancy terminations. prevailing sociopolitical climates. legal issues. medical techniques and procedures. and spatial components huve been investigated. 987
NORAH
988
F. HENRY and MILTON E. HARVEY
providers in some locales. Research on abortion accessibility and travel behavior of women seeking abortion indicates that accessibility in the home state. in neighboring states, and distance to be travelled are determining factors in abortion travel behavior Cl, 4.51. Taken together, the spatial pattern of abortion facility location, accessibility, inclination to travel, and distance to be travelled contribute to the spatial variation found in the rate of abortions performed. Rate variation also depends upon the metropolitan, social and demographic character of the area, and the attitudes of individuals. Social and political community norms contribute to a complex pattern of abortion behavior at the state level. Socio-political
research, especially on aspects of the spat&temporal changes in abortion rates across established political units. Examining the patterns of abortion rate variations across political units will help identify the political, social and economic variables that influence those rates. To adequately understand such processes. a dynamic approach which covers several time periods and involves the identification of the dominant spatial and socio-economic processes is necessary. A conceptualization for such a study is presented below. In subsequent sections a series of propositions developed from and tested.
SPATl040CIAL
DYNAMIC ABORTION
dimensions
Borders and Cutright identify several community variables which play a major role in abortion rate _variation. The number of agency types (hospital, clinic, physician’s office, etc.), number of providers per 10,000 women 15-44, and changes in the number of providers and number of agency types are the most powerful explanatory variables, but demographic and socio-economic variables also help explain SMSA abortion variations [6]. Benditt cites a modification in social and political climates as having permitted greater employment of *pregnancy termination [7-j. Arney and Trescher indicate that attitudes vary throughout the U.S., with age, level of education and religion important attitude determinants [8]. The role of popular attitudes in the abortion picture is unclear, however. While difficulties in establishing abortion services are created by physician and hospital refusals to perform or permit abortions, Henry found in a 1976 study of the northeastem United States that popular opposition to abortion facility location was not a major deterrent to facility location [2,9]. An unanswered question from this research, and from other abortion studies, is the role of social climate in abortion accessibility and rate variation. While this brief discussion of the distribution and determinants of abortion rates indicates that some progress has been made toward understanding certain aspects of this complex topic there is need for further
the conceptualization
are presented
PROCESSES AND
RATES
At any point in time, the number of abortions performed are the result of the aggregate decision making process of many women and various aspects of the prevailing political, social and economic institutional constraints. Where there are alternative abortion facilities spatial choice processes are also influential. In addition to these factors, we believe that rate variation also reflects the attributes of the facilitities. We believe that these three components-the contemporary political constraints. the spatial constraints. and the attributes of the facilities-control the spatial distribution of abortion rates. Each of these is discussed briefly below (see Fig. 1). The contemporary
political
atmosphere
The institutional constraints on abortion are multifaceted, reflecting the influence of national legal and political viewpoints. These viewpoints determine the development of new laws, the reinterpretation of existing laws, and the distribution of finances. The most sensitive indicators of these prevailing political viewpoints are the legislators who bridge local and national politics. Since there are more Congressmen and their tenure is shorter than that of Senators’, we believe that their legislative actions are far more reflective of their constituencies. The impact of local governments on abortion rates also is visible. Local legal, financial and social conditions, interactively, will create an atmosphere in
Fig. I. Conceptualization of impacts on abortion facility locations
and rates of provision.
Social. spatial and political
determinants
which it may be easy or difficult for a woman to have an abortion. Together, national and local concerns determine the (1) allocation of funds for abortion for the financially disadvantaged. (2) development of new legal measures, (3) re-interpretation of existing laws. and (4) group efforts to either aid or deter abortions. Consequently, abortion rates reflect the national and local political and social milieus. The spatial constraints
The selection of an abortion facility is conditioned by the woman’s information field about abortions. the availability of facilities, the distribution and alignment of transportation lines, and travel costs. The first factor highlights social influence and perhaps proximity; the second, third and fourth emphasize spatial continguity and friction of distance. We believe that rates of abortion vary because of these spatial forces. The abortion rate pattern reflects the number of facilities in the home state and continguous states, and the effects of distance decay and spatial contiguity. Availability qf service Service availability is directly related to the political and spatial components. For example, if legal interpretations are tending toward a liberalization of abortion laws, but new, more restrictive laws are created and financial appropriations are reduced,
(i) (ii)
Unavailability Predominantly
illegal
tei3IinatiOnS
sought (iii) Ill-equipped facilities accompanying morbidity/mortality
with
(i) (ii)
Decreased availability Longer travel distance and qreater expense for (iii) More illegal abortions (iv) Variation in service provision to various groups (poor, teenagers, etc.)
v:Mnen
(i) (ii)
Increased availability Shorter travel distances and less expense for women (iii) Fewer illegal abortions among some groups (iv) More even service accessibility by various groups (i) (ii)
Reduced abortion availability Increased travel distance and cost to women (iii) Increase in illegal abortions
(i) (ii)
Increase in availability Decreased travel distance and expense for uomen (iii) Decrease in illegal abortions (over time)
Fig. 2. Types
of U.S.
abortion
rates
989
abortion service availability would be affected. Such a situation would reduce the number of facilities within the state, thereby decreasing abortion availability; lead to longer travel distances for the woman and, thus, an increase in the cost of the service; encourage the seeking of illegal abortions, at greater risk to personal health; and increase the variation in service provision to specific subpopulations (see Fig. 2). On the other hand, the interpretation of existing laws to permit abortion, the passing of new legislation to extend or continue legal abortion and the inclusion of abortion funding in legislative financial packages would have a different impact. This more liberal political climate would increase the availability of abortion. The associated travel distance and costs will be reduced and an eventual decrease in the seeking of illegal abortions would result. In a static framework Fig. 2 shows that these three components may produce an abortion rate surface that reflects (1) regional differences in the distribution of services, (2) the tendencies in voting by Congressmen, and (3) the amount of money available for abortion for the disadvantaged. In a dynamic context the effects of these components become more complex. An understanding of the change in abortion rates over time is a necessary condition for assessing the impact of these components. Such observations are made in the next section.
(i) Few abortion clinics exist (ii) Few abortions perfoneed for (iii) Extra legal referral and abortion services exist
poor
I
I
I
I+
(i) More facilities coamience activities in previously restrictive states (ii) Few abortions performed for indigent at public expense (iii) Alteration in service policies with more liberal regulations
1
++
(i) Few clinics comnence activities (ii) Policy changes for existing facilities to continue (iii) Increased service provision to indigent
+
I+
(i) Facilities increase in number (ii) Services available to poor, teenaoers, married on less restricted basis (or unrestricted)
+
(i) Few clinics cofmience activity in isore restrictive states (ii) Fewer abortions performed at public cost for poor woiaen (iii) Change in service policies with restrictive laws, i.e. waiting periods, parental or spot&al consent
of political
constraints
and alternaie
strategies
in a state.
++
/
990
NORAH ORSERVATIOSS
ON ABORTION
F. HENRY and MILTON E. HARVEY
RATES
First, over time the ratio, r, of people who have had an abortion and those who have not. will increase toward an ‘optimal’ mix, k. Second, over an appreciable time period the increase in I’ toward k will follow a logistic curve. Third, because of operational differences of these three components in different states, the rate of convergence of r towards k varies. At any point in time different states will be at various stages of the logistic curve. Fourth, and directly as a result of the third, the variations in the abortion rates at any time reflect the spatial manifestations of developed and developing logistic curves. Finally, because of the sim-
1975
ultaneous operation of the three components discussed above, certain states will exhibit similar patterns of abortion rates. These spatial tendencies (see Fig. 3) are summarized below: (a) New York, California and Washington have consistently high abortion rates. These we have called the lead states. (b) Over time. states proximal to those with high rates in the previous time period tend to have successively higher rates in following time periods. (c) Rates tend to be consistently higher on the western and eastern peripheries of the nation. (d) The rates of increase between successive time
1976
Legend Abortions
per E m
1.000
Woman
oges 15-44
7.2 0I - 14.40 7.20 14.41 -21.60 21.61-30DO over
0 200 L I Mules
Fig. 3. U.S. abortion rates. Source: Ahorrion Suraeilltrtw. U.S.P.H.S.
30.00
400 I
bl
Social. spatial and political determinants of U.S. abortion rates periods for lead states (those with early and with consistently high rates) are relatively low. (e) Because of the time intervals used, minor fluctuations in the rates of increase between successive time periods are generally low: This is especially true of lead states. While it is evident that the changes in abortion rates in states generally have been gradual rather than precipitous, a number of questions emerge regarding abortion rates within the United States. From a spatial perspective, what are the dimensions to those rate changes? What is the so&-political interplay in determining the rate of abortion? It is to these questions that the remainder of this paper is addressed. SOCIO-SPATIO-POLITKXL
PROPOSITIONS
ON ABORTION
Based upon the social, spatial and political dimensions of abortion discussed above. the following specific hypotheses are proposed and examined: (a) Spatially, abortion rates decrease with distance from centers that are at a later stage of the logistic curve. (b) Because of the strong political influences in regional subsystems, states within subregions will have similar abortion rates. (c) The abortion rates will be higher in states where there is a larger percentage of the population residing in urban areas, where per capita abortion providers are greater in number, where costs are lower, and where the sociopolitical views are more liberal. This proposition states that the variations in abortion rates can be explained in terms of providers, economics, and socio+olitical considerations. These three propositions are grouped into two broad categori.es. The first two, (a) and (b) constitute the spatial component; (b) and (c) constitute the sociopolitical component. For testing these propositions, data on abortion rates and associated social, economit and political data were collected for the United States for a 5 year period, 1973-1977. METHODOLOGICAL
CONSIDERATIONS
The District of Columbia was excluded because of its uniquely urban nature and because the data pertaining to current sociopolitical issues were reflected in the social and political positions represented by the remaining jurisdictions. Alaska and Hawaii were eliminated from the analysis due to their unaccessible locations which essentially removed them from the spatial domains and cognitions of the women located outside their respective borders. Nature und sou~ccs of data
The data employed in this study were both direct measures. The directly measured variables included: (1) the number of abortion providers per 1000 women 15-44 (PROV): (2) the average cost of abortion (COST): (3) the percent of a state’s resiin a different jurisdiction dents seeking abortion (LV); (4) the annual status of ERA ratification (ERA); and (5) the degree of urbanization in individual states (URB). utilized as a measure of metropolitanism. Surand surrogate
991
rogate measures of social climate included: (1) an index which reflected via U.S. Senate voting behavior, the general statewide socio-political attitude toward abortion (SEN); (2) a similar index utilizing U.S. Congressional voting behavior, which reflected a composite of local-lewl sentiments regarding abortion (HSE). These indices reflect the percent of the Senators and Congressmen who voted for restrictive federal funding for medicaid abortions for each state, respectively. In addition to these variables, various measures of distance and contiguity will be developed and used to calibrate several aspects of the spatial constraint dimension. Thus, abortion rate variation for the United States is explained in terms of providers, economics. and sociopolitical considerations, and spatial constraints. The method of analysis
For assessing the annual change in abortion rates a standardized index, &. was developed for each state for each of the four time periods: 1973-1974, 1974-1975, 1975-1976 and 19761977. Using these z-scores, four categories of states were identified based upon their respective scores. These categories were: (1) -9.99 < ditk d - 1.96 significantly lower national rate (Type A) lower (2) - 1.96 < dige C 0.00 negligibly national rate (Type B) (3) 0.00 -Z dig,,< 1.96 negligibly higher national rate (Type C) (4) 1.96 < ditk < 9.99 significantly higher national rate (Type D).
than than than than
To test the assertion that there are regional patterns to abortion a three-stage process was used. First, the data on abortion in the 48 states were standardized and grouped using Wards H Group, a hierarchical classification technique which seeks to maximize between group variation and minimize within group differences [lo]. Three groups of states with ‘similar’ growth profiles in the rates of abortion were identified. Second, the averages for each of these three groups were computed and plotted. Third, a logistic curve was fitted to the average abortion rates. r, for the three groups. Because there will always be an appreciable number of non-adoptors in any state, the hypothesized logistic curve will move toward an asymptote, k, with k less than unity. The equation is r = k/( 1 + e(“-h’)).
(1)
For this study k was set to 0.34, a value slightly higher than the largest average abortion rate for the lead states. It is assumed that the relatively stable abortion rates for these lead states imply that they are ‘close’ to the maximum ratio of abortions per 1000 women 15-44 that will exist in any state under the prevailing socio-economic atmosphere. For any time period the rate of abortion can be computed from (1). dr/dt = hr(l - r/k).
(2)
Previous abortion research has revealed the impact of spatial contiguity on the number of abortion facilities located in an area. Cities located close to New York and Chicago. for example. had more abortionperforming facilities than cities located at great dis-
992
NORAH
F.
HENRY and MILTON E. HARVEY
tames from these two urban centers. In addition, larger urban centers tended to have abortion facilities operational relatively soon after abortion was legalized. Thus, abortion-facility location has been conceptualized as a diffusion process [Z]. Here a similar conceptualization is employed for state abortion rates. That is, those states located distantly from high abortion rate states will tend to have low abortion rates. A regional pattern to abortion rates, then, is discernible with certain high nodes and certain low regions. Testing of the second spatial proposition entails the identification of ‘lead’ nodes and the development of models to capture both distance decay ahd neighborhood effects. While change in abortion rates at these lead states will be minimal, the distance decay hypothesis asserts that the abortion rates of surrounding states will decrease with distance from the lead states. Assuming that there are n such centers, this proposition was tested using the following equation:
In ri, = In (I - bDf + i
C,D,, +
!=1
i
eD,jDf
j=I
(3)
where DC = min Cdl,, 42,
. . .,&Jr
h = the distance from i to lead state j, and a, b, c,,
and ei are parameters. To incorporate the.neighborhood effect into (3), we assume that the abortion rate in a state i will be a function of the abortion rates for the contiguous states. That is ril = f(r,,)
where j = 1,2, . . . , p.
(4)
Because of the variation in p for each of the states, (4) can be modified so that the rate at i is a function of the average in the contiguous states. Thus (4) becOllp3 h
= fk.,).
(9
With this, and introducing the interactive distance decay and contagion, (3) becomes: In rII = In a - bDf + i
j=l
+
w.r
CjDii + i
effects of
While abortion rates increased from 19731977, the annual rate increase in each state generally was not precipitous (see Table 1). The spatial pattern of annual abortion rate changes, illustrated by the respective z-score distributions (see Fig. 4) showed few significant deviations from the national rate of change between any two consecutive time periods, Spatially, those areas having rate increases significantly larger than the national rate of increase were Southern and Plains states. For example, rates of change significantly higher than the national average for 1973-1974 were found for Oklahoma and Utah. For 1974-1975 North Dakota, Louisiana, and Mississippi had significantly higher-than-average growth rates. West Virginia was the lone jurisdiction to exhibit a significant rate of increase between 1975 and 1976. The 19761977 rates of increase for West Virginia, Mississippi, Alabama, and Nevada were significantly greater than the national average. An interesting spatial pattern emerges for those states with abortion rate changes not. significantly greater than the average. With the exception of Maine and Vermont, those states with rates of increase minimally higher than the national average had a tendency to be clustered around the states with significant rate increases. Again, the spatial pattern had a Southern-plains bias. Regionally. then, it is possible to identify Southeastern and Plains as areas where rates of growth of abortion were increasing relatively faster than evident in the rest of the United States (see Fig. 4). While no jurisdiction displayed a rate significantly lower than the national average, those states with less than average rates of increase largely occupied the eastern and western coastal peripheries. The spatial bias evident in the comparison of individual state rate changes with the national rate change, on an annual basis, suggests the importance of distance and spatial contiguity in jurisdictional abortion rates, and the importance of sociopolitical constraints as determinants of abortion. Each of these is addressed below.
i f,D@f’r.r. I=1
Distance and sputial contiguity (6)
Equation (6) was fitted for each of the 5 years, 1973-1977, using a stepwise regression model. In each case the model selected was the last step at which the overall model was significant at the 0.05 level of confidence. Finally, Ordinary Least Squares (OLS) Regression was utilized to explain the integrated socio-politicalspatial dimensions of the state abortion rates for each year of the study. The following general model, derived from the previously described variables, was employed. R = a + b,ERA + b2URB + h,HSE + b$EN +bsPROV
Rate changes and regional patterns
eiDl,Df
i=I +
RESULTS
+ b,COST + b,LV.
(7)
The results of these analyses are presented in the following sections.
A number of observations may be made based upon the H Grouping and logistic curve procedures. discussed earlier. Clearly, the three groups of states have different growth rates (see Fig. 5). Spatially, the three states with consistently high rates are on the east and west coasts (New York, California and Washington). States experiencing early and continuously increasing growth in abortion rates generally were in the interior and also include the larger, more urbanized southern fringe states. The jurisdictions with continuously low abortion rates throughout the study period also were clustered, with several subregions identifiable. The New England Fringe, The Deep South, and The Plains-Rockies-High Plateau are three well-defined areas which emerged with relatively low rates of abortion throughout the study period. An additional, more amorphous region was identified within the eastern interior involving Iowa, Indiana, and West Virginia which had similarly low early rates in comparison with other jurisdications.
Social. spatial and political determinants
of U.S. abortion rates
993
Table 1. Summaries for changes in abortion rates by type Phase
Interval
Type A
Type B
Type C
Type D
1973-1974 1974-197s 197.5-1976 19761977 1973-197s 1974-1976 1975-1977 1973-1976 1974-1977 1973-1977
1 1 1 1 2 2 2 3 3 4
0 0 0 0 0 0 0 0 0 0
41 40 42 27 41 40 42 41 40 41
5 5 5 17 5 5 5 5 5 5
2 3 1 4 2 3 1 2 3 2
The results of the logistic analysis indicate that equation (2) fits the data. For states in the earlier part of the logistic curve the average abortion rate increases for the five time periods are 0.008, 0.0144, 0.0211, 0.0283 and 0.0296, respectively. Although increasing, they are markedly lower than the rate increases for those states in the middle of the adoption curve, with comparable rates of 0.0338, 0.0382, 0.0397, 0.0400 and 0.0351. Notice that the rates first increase, then decrease. In contrast, the rate increases for the
lead states decrease continuously as the asymptote is approached. The values are 0.0213, 0.0123, 0.0113, 0.0113 and 0.0032, respectively (see Fig. 5). An interesting spatial pattern emerges when the states with similar growth profiles are identified on a map. Not only is clear regional identification possible, but also the impact of contiguity and distance, examined via stepwise regression in the following section, are made more visible. Specifically, the lead states of California, Washington, and New York are
1976-77
1975 - 76
Legend 2 - score
9
2yo Miles
,400
0
-9.99
-
-1.96
m
_,,S5
-
0.00
m
0.0, 1.97 Fig.
-
= Significantly = Negligibly
1.96 = Negllglbly 9.99
= Significantly
lower lower
higher
than
than
than
higher
the the
the than
4. Abortion rate changes 1973-1977.
national
nation01
1 type
A)
rate
rate
(type
B)
rate
(type
Cl
nOtiOnal the
nOtiOnOl
rate
( type D)
994
NORAH
,
0.30
- y’
0.25
-
In :
F.
HENRY and MILTON E. HARVEY
I-0
tre
0”
(3.426-0.4711) I *o.s525t 1 1 I I I
I I
I I I
I I
I I I
I 1 1 Q
0.001
1
’
’
2
f
EL L ma,amma
42_
’
”
’
’
r r
--___-__-
’
11 ’
’
kizf 2 P mmmm Time,
AVERAGE
RATES
6 States
in Group in Group in Group
l
e
States States
’
’
FOR :
I (N-3) 2 (N-30) 3 (N-15)
1
’
E 2: 0) EE
t
Fig. 5. Rates of abortion as a function of time (a composite for the three types of states).
contiguous to states in the second category--the middle rate, steeply increasing states. The category three states-low early rates increasing over timeare contiguous to the category two states. These spatial similarities in growth rates are examined mathematically for each year. The result of the regression, presented in the next section, illustrates more clearly the influence of spatial propinquity for each. through time. Distance and contiguity
The stepwise regression results (see Table 2) indicate that important spatial factors-distance decay
and contiguity-are operational. With the exception of 1974. the results show that abortion rates declined with distance from the nearest lead state. In two specific years (1974 and 1977) nearness to one of these lead states had a significant influence on the abortion rates of neighboring states. In 1974 the states around California had relatively higher abortion rates. At the same time, however, those rates declined significantly with distance from the state of California. To a lesser degree, this tendency was replicated in 1977 with Washington State as the lead location. The absence of such a strong regional distance decay effect around New York may
Table 2. Stepwise regression results: relationship between rates of abortion and spatial determinants Independent variables 1. Minimum distance from the closest lead state
1973
1974
-0.0190’ (2.148)
1975
1976
1977
-0.01948 (2.199)
0.009* (2.743)
-0.012* (2.132)
2. Closest to New York 3. Closest to California
0.299* (2.947)
4. Closest to Washington
0.2147* (3.408)
5. Proximity to New York
9. 10. 11. 12.
0.004 (0.565)
- 0.209 (1.784)
6. Proximity to California 7. Proximity to Washington State 8. Average rate in ail continguous
0.0213 (0.749)
0.0297 (1.939)
0.037 (1.319)
0.015 (1.591)
0.023 (1.151)
1.945
1.977 0.479’
2.686 0.438.
2.5601 0.3971
Average rate for states closest to New York Average rate for states closes to California Average rate for states closest to Washington Constant
R’ Values
0.367*
3.159 0.341’
are b-values. Their associated t-values are in parenthesis. Blanks imply the variable did not ‘enter’ the regression.
*Significant at the 0.05 level of confidence.
Social. spatial and political determinants of U.S. abortion rates reflect the fact that such processes may have occurred in the east in 1970-1973. when numerous eastern states were liberalizing their abortion statutes. As this analysis covers the 5 years 1973-1977. this apparent aberration in the system may have been missed. The regional patterns characteristic of abortion rates and relative changes in abortion rates throughout the study period may reflect the cultural, social and political ties between spatially contiguous states. That is, the shared social-cultural-political framework between states which often prompts their regional identification and categorization may contribute to explaining the regional patterns which emerge when examining annual abortion rates. Thus, while the significant b-values indicate that continguity and distance explain an appreciable amount of the variation in abortion rates across states, these distance variables may also reflect important historical sociocultural, political similarities. Socio-political determinants
The variables significant in explaining abortion rates were similar over the study years (see Table 3). Both social and political components were evident. however, neither Senate nor House voting behavior was influential in predicting abortion rates. Neither was the economic variable, mean abortion cost, which was included in the 1976 and 1977 models (the only years for which such data were available) a significant predictor. The effects and significance of the individual predictors varies over the study years. 1973 Abortion rates The analysis reveals that two variables were important in explaining abortion rate variation in 1973 (see Table 3). The percent of women obtaining abortions outside the state of residence and the per capita number of abortion providers in a state were strong predictors of abortion rates. As the number of providers increased the abortion rate increased. An inverse relationship existed between the abortion rate and the percent of women who secured abortions out
Table 3. Sock-political Independent 1.
Annual status of ERA ratification
2. no Leaving state for abortion
3. % Urban 4. Number of providers/l000
women 15-44
5. Senate voting behavior 6. Congressional
of state. As the percent of women securing abortions outside their home states decreased, the abortion rate for the state increased. These variables indicate that a state with comparatively few providers of abortion services and‘a relatively large number of women leaving the state to obtain abortions will have a low abortion rate. Similar results were found for the 1974 state abortion rates. 1974 Abortion rates The results indicate the importance of three variables. Similar to 1973, the percent leaving the state of residence to obtain abortions and the per capita number of abortion ‘providers were important explanatory variables. The percent of the state’s population residing in urban areas also was important in 1974. With a low rate of seeking abortions outside the state of residence and a high per capita number of abortion providers, a state’s abortion rate was higher in 1974. The urban bias characterizing the spread of technological innovation emerged in 1974. High rates of urbanization resulted in higher rates of abortion in 1974. The same variable contributed to explaining the 1975 state abortion rate variation. 1975 Abortion rates The percent of the women securing abortions outside of their home states. the level of urbanization, and the per capita number of providers continued to be important variables in explaining the 1975 abortion rate. The 1975 abortion rate was higher in states where the urbanized population was proportionately larger, where the per capita number of providers was higher and the percentage of women seeking abortion outside the state was low. A discussion of these results is incomplete without mention of the ERA ratification. While not significant at the selected 0.05 level. ratification of the equal rights amendment contributed to the model and should be noted. The results for 1975 are consistent with the 1973 and 1974 results.
determinants
variables
voting behavior
7. The average cost of abortion 8._.Constant R’
F value
*Significant at least at 0.05 level (r-values). NA signifies data not available for inclusion into model
995
of abortion rates: the results 1973 3.18 (1.59) -0.128 ( - 3.70) 0.05 (1.33) 93.14* (2.24) NS -2.11 (70.47) NA
1974
1975
2.08 2.76 (1.31) (1.84) -0.09* -0.012* ( - 2.62) (-3.17) 0.09* 0.09* (2.50) (3.60) 12.19* 8.13* (3.55) (4.04) - 2.08 - 2.77 ( - 1.27) (- 1.09) NA I .22 (0.44) NA NA
8.00
4.23
5.81
0.60
0.66
0.68
12.69*
13.17*
16.84*
1976
1977
3.25* (1.96) -0.12*
0.16 (0.38) -0.07 ( 1.46) 0.18’ (5.38) 8.44” (3.13) 2.30
( -G2’* (3.76) 6.168 (2.35) 0.20 (-0.10) - 2.43 (-0.88) - 0.06 ( - 0.66) 8.61 0.66 1I.038
t 1.24)
0.69 12.61*
NORAH
996 1976
F. HENRYand MILTONE. HARVEY
Abortion rates
For 1976 the result reveals the importance
of Social and political variables in explaining abortion rates. Similar to the 1973-1975 findings, a higher abortion rate in 1976 was attributable to a higher per capita number of providers, a high level of urbanization. a low rate of obtaining abortions outside the home state, and a political variable. Ratification of the ERA was significantly associated with a higher rate of abortion in 1976. 1977 Abortion rules
Unlike the three previous years, in 1977 the variation in abortion rate was attributable to only two variables. Similar to the 1973 results, the degree of urbanization and the provider ratio were the significant predictors of abortion rates. As the level of urbanization and the per capita number of providers increased, a state was more likely to have a higher rate of abortion. These regression results reveal the importance of political dimensions in abortion rates and some underlying spatial, social and political attributes (see Table 3). Between 1973 and 1976 the percent of abortions obtained outside the state of residence was an important explanatory variable in accounting for rate variations. During the entire study period (19731977) the provider ratio also was an important predictor. A large per capita nuniber of abortion providers resulted in a higher rate of abortion. These variables indicate that if abortion facilities exist they will be utilized and if they do not exist in a given locale. they will be found elsewhere. From 1974 to 1977 the level of urbanization in a state was an important predictor of abortion rates. In 1975 a statistically weak interrelationship was found between ratification of the equal rights amendment and a state’s abortion rate. This interrelationship continued to 1976, when ERA ratification was an important explanatory variable. Over time the effects of the individual variables show interesting changes. First, although not statistically significant. the influence of the status of the ERA on abortion rates generally declined (except in 1976) from 1973 to 1977. As more states approved the ERA its effect on abortion decreased. Second, and directly related to the first, is the change in the significance of the percent leaving a state for abortion on abortion rates. By 1977 this was no longer a significant factor. Third, the influence of urbanization on these rates has increased. In fact, the increase in abortion rates with urbanization more than tripled from 1973 to 1977. Fourth, the number of abortion providers per I&MI women 15-44 continued to influence abortion ‘rates significantly. Over time, however, as the number of facilities increased in the states. the rate of abortion increase attributable to this factor declined. SUMMARY
AND CONCLUSIONS
Abortion rates in most states in the U.S. increased following the 1973 Supreme Court decision. A regional pattern to the rate changes emerged with Plains and Southern states having abortion rate
changes significantly higher than the rate increase for the United States as a whole. A distance function was related to these rate changes. Where abortion got an early start, 1970-1973, in some eastern and western states, annual state rate changes were generally less than the national rate increase for the study period. Relatively small increases in abortion rates were visible in states contiguous to these lead states for the 1973-1977 study period, largely because these adjacent states had relatively high abortion rates soon after abortion was legalized. Those states not immediately adjacent to the eastern and western lead states. the Southern and Plain states in this study, experienced relatively low abortion rates and large rate increases for the study period. The abortion rate increase in these three identifiable groups of states, i.e. the lead states, the majority states, and the laggards, conform reasonably well to the logistic curve. Proximity to the lead states had significant influence on abortion rates in adjoining states. This spatial contiguity, reinforced by social. cultural and political history, resulted in regionally discernible abortion rates, explainable by socio-political variables. While certain believable social, spatial and political dimensions to abortion rates for the United States are revealed here, several questions remain. What will be the impact upon abortion rates of the more conservative Congress? Is there spatial similarity to popular attitudes toward abortion? Are these popular attitudes reflected in state abortion rates? Are age-specific state abortion rate variations similar to overall abortion rates? Future researchers into the abortion issue and its spatial dimensions may want to consider these questions. REFERENCES
1.
Forrest J. D.. Sullivan E. and Tietze C. Abortion in the United States, 1977-78. Family 329-341, 1979.
P/am.
Perspcct.
11,
2. Henry N. F. The diffusion of abortion facilities in the 3. 4.
5. 6. 7. 8. 9.
northeastern United States. 1970-1976. Sot. Sci. Med. ItD, 7-15, 1978. Sullivan E.. Tietze C. and Dryfoos J. G. Legal abortion in the United States. 19751976. Family P/arm. Perspeer. 9, 116-129. 1977. Henry N. F. Responses to a post-abortion questionnaire: spatial. social and contraceptive issues. Unpublished Report Prepared for Planned Parenthood of Broome and Chenango Counties. New York. 1980. Shelton J. D., Brann E. A. and Schulz K. F. Abortion utilization: does travel distance matter? Family Plann. Perspect. 8, 260-262. 1976. Borders J. A. and Cutright P. Community determinants of U.S. legal abortion rates: family Pfunn. Prrspect. Il. 227-233. 1979. Benditt J. Second-trimester abortion in the United States: Special Report in Family Phnn. Prrsprcr. Il. 358-361. 1979. Arney W. R. and Trescher W. H. Trends in attitudes toward abortion. Fumily Plann. Perspect. 8. 117-124. 1976. Callahan D. Abortion and government polity. fami/) Plunn.
Perspect.
I I, 275-279.
1979.
‘IO.Ward J. H. Jr. Hierarchical grouping to optimize an objective function. Am. starisr. Ass. J. 236-244.
1963.
Sot. &I. Med. Vol. 16. pp. 987 IO 996. 1982 Pruned in Great Britain.All rights reserved
SOCIAL, SPATIAL AND POLITICAL DETERMINANTS U.S. ABORTION RATES
OF
NORAH F. HENRY’ and MILTON E. HARVEY’ ’ Department of Geography, State University of New York at Binghamton, NY 13901 and
‘Department
of Geography. Kent State University, Kent, OH 44242. U.S.A.
Abstract-Abortion rates in the United States have risen annually since the 1973 Supreme Court decision. The regions with the greatest rate increases are the Southern and Plains states; the lowest rate increases were in regions which had high abortion rates soon after abortion was legalized. While spatial contiguity appears to influence abortion rates. that is. states with high rates of abortion are clustered spatially. social and political influence are also evident. Ratification of the equal rights amendment. the seeking of abortion outside the state of residence, and the degree of urbanization within a state are variables which influenced U.S. abortion rates between 1973 and 1977.
INTRODUCTION
In the 1960s increased social consciousness, advances in medical technology, and third party payment programs increased the technical quality of health care and the numbers and groups of persons to whom services were provided. One group to benefit from the increased attention was women. Advances in medical technology provided safer. more effective modes of birth control. Sophisticated monitoring devices could be employed to detect in utero fetal distress and pregnancy termination procedures were developed which mitigated previous difficulties in abortion. Of these medical services abortion has attracted considerable attention. The number of abortions performed in the United States has increased dramatically since the 1960s. Most of the increase occurred following the 1973 Court decision. However, despite the legality of abortion. differences in abortion rates persisted through the 1970s. The purpose of this paper is to investigate the spatial diversity in abortion rates in the United States between 1973 and 1977. Understanding the diversity present in the rates of abortion involves examination of political, social, economic. and spatial constraints. A comprehensive treatment of their collective impact upon abortion rates is lacking. despite the range of topics included in abortion studies. This paper (a) examines the changes in abortion rates in the coterminous United States, and (b) assesses the relative importance of spatial, political and social determinants in the distribution of abortion rates. ISSUES IN ABORTION
Spatial components of abortion have been examined by both geographers and non geographers. The findings of this research, detailed below, .indicate clearly a spatial bias in abortion-facility location and in abortion accessibility. Spatial dimensions
Spatial components of abortion which have been investigated include: (1) the relationship between metropolitanism, abortion rates and locations of abortionists; (2) locational inequities: (3) the process by which facilities spread; and (4) patient travel behavior. A high metropolitan concentration of abortion facilities exists, with west coast and northeastern urban centers displaying the greatest concentrations [l, 2). Abortion clinics provide more abortions than do other types of facilities (i.e. hospital, private physicians), and are generally found within urban areas. The increase in the number of clinics has been related to the increase in abortion rates in the ten SMSAs with the largest increases in abortion rates [3]. The metropolitan aspect is only one issue in abortion facility location and abortion accessibility. Location of abortion facilities in the United States generally has followed the urban hierarchy. In larger urban areas abortion facilities were established shortly after abortion was legalized. Establishment of these early facilities was followed by (1) an increase in number of facilities at the initial locations. and (2) the location of new facilities in smaller urban centers [2]. However, spatially abortion services are not uniformly available in urban areas, nor equally accessible within states. While ail states have at least one facility which will provide pregnancy termination at the request of the woman. there is considerable variation in the. number of providers and the number provided for. In 1977, for example. 2387 (77”/;,of all U.S.) counties had no,abortionist identified with them Cl]. The inability to secure an abortion easily in her home area may lead a woman to travel to a different locale where abortion is more readily available. In 1977 approx. 9“, of all U.S. abortions were performed outside the state of residence. While this represents a substantial decrease from 25.2O,,in 1973 and 43.8:” in 1972. it continues to illustrate a shortage of abortion
STUDIES
Abortion has received a tremendous amount of attention in the literature and has been the procedure on which the greatest amount has been published. Topically. the scope of abortion studies has been wide. Analysis of the demographic characteristics of abortion patients. abortion-rate differentials. the availability of abortion to women desiring pregnancy terminations. prevailing sociopolitical climates. legal issues. medical techniques and procedures. and spatial components huve been investigated. 987
NORAH
988
F. HENRY and MILTON E. HARVEY
providers in some locales. Research on abortion accessibility and travel behavior of women seeking abortion indicates that accessibility in the home state. in neighboring states, and distance to be travelled are determining factors in abortion travel behavior Cl, 4.51. Taken together, the spatial pattern of abortion facility location, accessibility, inclination to travel, and distance to be travelled contribute to the spatial variation found in the rate of abortions performed. Rate variation also depends upon the metropolitan, social and demographic character of the area, and the attitudes of individuals. Social and political community norms contribute to a complex pattern of abortion behavior at the state level. Socio-political
research, especially on aspects of the spat&temporal changes in abortion rates across established political units. Examining the patterns of abortion rate variations across political units will help identify the political, social and economic variables that influence those rates. To adequately understand such processes. a dynamic approach which covers several time periods and involves the identification of the dominant spatial and socio-economic processes is necessary. A conceptualization for such a study is presented below. In subsequent sections a series of propositions developed from and tested.
SPATl040CIAL
DYNAMIC ABORTION
dimensions
Borders and Cutright identify several community variables which play a major role in abortion rate _variation. The number of agency types (hospital, clinic, physician’s office, etc.), number of providers per 10,000 women 15-44, and changes in the number of providers and number of agency types are the most powerful explanatory variables, but demographic and socio-economic variables also help explain SMSA abortion variations [6]. Benditt cites a modification in social and political climates as having permitted greater employment of *pregnancy termination [7-j. Arney and Trescher indicate that attitudes vary throughout the U.S., with age, level of education and religion important attitude determinants [8]. The role of popular attitudes in the abortion picture is unclear, however. While difficulties in establishing abortion services are created by physician and hospital refusals to perform or permit abortions, Henry found in a 1976 study of the northeastem United States that popular opposition to abortion facility location was not a major deterrent to facility location [2,9]. An unanswered question from this research, and from other abortion studies, is the role of social climate in abortion accessibility and rate variation. While this brief discussion of the distribution and determinants of abortion rates indicates that some progress has been made toward understanding certain aspects of this complex topic there is need for further
the conceptualization
are presented
PROCESSES AND
RATES
At any point in time, the number of abortions performed are the result of the aggregate decision making process of many women and various aspects of the prevailing political, social and economic institutional constraints. Where there are alternative abortion facilities spatial choice processes are also influential. In addition to these factors, we believe that rate variation also reflects the attributes of the facilitities. We believe that these three components-the contemporary political constraints. the spatial constraints. and the attributes of the facilities-control the spatial distribution of abortion rates. Each of these is discussed briefly below (see Fig. 1). The contemporary
political
atmosphere
The institutional constraints on abortion are multifaceted, reflecting the influence of national legal and political viewpoints. These viewpoints determine the development of new laws, the reinterpretation of existing laws, and the distribution of finances. The most sensitive indicators of these prevailing political viewpoints are the legislators who bridge local and national politics. Since there are more Congressmen and their tenure is shorter than that of Senators’, we believe that their legislative actions are far more reflective of their constituencies. The impact of local governments on abortion rates also is visible. Local legal, financial and social conditions, interactively, will create an atmosphere in
Fig. I. Conceptualization of impacts on abortion facility locations
and rates of provision.
Social. spatial and political
determinants
which it may be easy or difficult for a woman to have an abortion. Together, national and local concerns determine the (1) allocation of funds for abortion for the financially disadvantaged. (2) development of new legal measures, (3) re-interpretation of existing laws. and (4) group efforts to either aid or deter abortions. Consequently, abortion rates reflect the national and local political and social milieus. The spatial constraints
The selection of an abortion facility is conditioned by the woman’s information field about abortions. the availability of facilities, the distribution and alignment of transportation lines, and travel costs. The first factor highlights social influence and perhaps proximity; the second, third and fourth emphasize spatial continguity and friction of distance. We believe that rates of abortion vary because of these spatial forces. The abortion rate pattern reflects the number of facilities in the home state and continguous states, and the effects of distance decay and spatial contiguity. Availability qf service Service availability is directly related to the political and spatial components. For example, if legal interpretations are tending toward a liberalization of abortion laws, but new, more restrictive laws are created and financial appropriations are reduced,
(i) (ii)
Unavailability Predominantly
illegal
tei3IinatiOnS
sought (iii) Ill-equipped facilities accompanying morbidity/mortality
with
(i) (ii)
Decreased availability Longer travel distance and qreater expense for (iii) More illegal abortions (iv) Variation in service provision to various groups (poor, teenagers, etc.)
v:Mnen
(i) (ii)
Increased availability Shorter travel distances and less expense for women (iii) Fewer illegal abortions among some groups (iv) More even service accessibility by various groups (i) (ii)
Reduced abortion availability Increased travel distance and cost to women (iii) Increase in illegal abortions
(i) (ii)
Increase in availability Decreased travel distance and expense for uomen (iii) Decrease in illegal abortions (over time)
Fig. 2. Types
of U.S.
abortion
rates
989
abortion service availability would be affected. Such a situation would reduce the number of facilities within the state, thereby decreasing abortion availability; lead to longer travel distances for the woman and, thus, an increase in the cost of the service; encourage the seeking of illegal abortions, at greater risk to personal health; and increase the variation in service provision to specific subpopulations (see Fig. 2). On the other hand, the interpretation of existing laws to permit abortion, the passing of new legislation to extend or continue legal abortion and the inclusion of abortion funding in legislative financial packages would have a different impact. This more liberal political climate would increase the availability of abortion. The associated travel distance and costs will be reduced and an eventual decrease in the seeking of illegal abortions would result. In a static framework Fig. 2 shows that these three components may produce an abortion rate surface that reflects (1) regional differences in the distribution of services, (2) the tendencies in voting by Congressmen, and (3) the amount of money available for abortion for the disadvantaged. In a dynamic context the effects of these components become more complex. An understanding of the change in abortion rates over time is a necessary condition for assessing the impact of these components. Such observations are made in the next section.
(i) Few abortion clinics exist (ii) Few abortions perfoneed for (iii) Extra legal referral and abortion services exist
poor
I
I
I
I+
(i) More facilities coamience activities in previously restrictive states (ii) Few abortions performed for indigent at public expense (iii) Alteration in service policies with more liberal regulations
1
++
(i) Few clinics comnence activities (ii) Policy changes for existing facilities to continue (iii) Increased service provision to indigent
+
I+
(i) Facilities increase in number (ii) Services available to poor, teenaoers, married on less restricted basis (or unrestricted)
+
(i) Few clinics cofmience activity in isore restrictive states (ii) Fewer abortions performed at public cost for poor woiaen (iii) Change in service policies with restrictive laws, i.e. waiting periods, parental or spot&al consent
of political
constraints
and alternaie
strategies
in a state.
++
/
990
NORAH ORSERVATIOSS
ON ABORTION
F. HENRY and MILTON E. HARVEY
RATES
First, over time the ratio, r, of people who have had an abortion and those who have not. will increase toward an ‘optimal’ mix, k. Second, over an appreciable time period the increase in I’ toward k will follow a logistic curve. Third, because of operational differences of these three components in different states, the rate of convergence of r towards k varies. At any point in time different states will be at various stages of the logistic curve. Fourth, and directly as a result of the third, the variations in the abortion rates at any time reflect the spatial manifestations of developed and developing logistic curves. Finally, because of the sim-
1975
ultaneous operation of the three components discussed above, certain states will exhibit similar patterns of abortion rates. These spatial tendencies (see Fig. 3) are summarized below: (a) New York, California and Washington have consistently high abortion rates. These we have called the lead states. (b) Over time. states proximal to those with high rates in the previous time period tend to have successively higher rates in following time periods. (c) Rates tend to be consistently higher on the western and eastern peripheries of the nation. (d) The rates of increase between successive time
1976
Legend Abortions
per E m
1.000
Woman
oges 15-44
7.2 0I - 14.40 7.20 14.41 -21.60 21.61-30DO over
0 200 L I Mules
Fig. 3. U.S. abortion rates. Source: Ahorrion Suraeilltrtw. U.S.P.H.S.
30.00
400 I
bl
Social. spatial and political determinants of U.S. abortion rates periods for lead states (those with early and with consistently high rates) are relatively low. (e) Because of the time intervals used, minor fluctuations in the rates of increase between successive time periods are generally low: This is especially true of lead states. While it is evident that the changes in abortion rates in states generally have been gradual rather than precipitous, a number of questions emerge regarding abortion rates within the United States. From a spatial perspective, what are the dimensions to those rate changes? What is the so&-political interplay in determining the rate of abortion? It is to these questions that the remainder of this paper is addressed. SOCIO-SPATIO-POLITKXL
PROPOSITIONS
ON ABORTION
Based upon the social, spatial and political dimensions of abortion discussed above. the following specific hypotheses are proposed and examined: (a) Spatially, abortion rates decrease with distance from centers that are at a later stage of the logistic curve. (b) Because of the strong political influences in regional subsystems, states within subregions will have similar abortion rates. (c) The abortion rates will be higher in states where there is a larger percentage of the population residing in urban areas, where per capita abortion providers are greater in number, where costs are lower, and where the sociopolitical views are more liberal. This proposition states that the variations in abortion rates can be explained in terms of providers, economics, and socio+olitical considerations. These three propositions are grouped into two broad categori.es. The first two, (a) and (b) constitute the spatial component; (b) and (c) constitute the sociopolitical component. For testing these propositions, data on abortion rates and associated social, economit and political data were collected for the United States for a 5 year period, 1973-1977. METHODOLOGICAL
CONSIDERATIONS
The District of Columbia was excluded because of its uniquely urban nature and because the data pertaining to current sociopolitical issues were reflected in the social and political positions represented by the remaining jurisdictions. Alaska and Hawaii were eliminated from the analysis due to their unaccessible locations which essentially removed them from the spatial domains and cognitions of the women located outside their respective borders. Nature und sou~ccs of data
The data employed in this study were both direct measures. The directly measured variables included: (1) the number of abortion providers per 1000 women 15-44 (PROV): (2) the average cost of abortion (COST): (3) the percent of a state’s resiin a different jurisdiction dents seeking abortion (LV); (4) the annual status of ERA ratification (ERA); and (5) the degree of urbanization in individual states (URB). utilized as a measure of metropolitanism. Surand surrogate
991
rogate measures of social climate included: (1) an index which reflected via U.S. Senate voting behavior, the general statewide socio-political attitude toward abortion (SEN); (2) a similar index utilizing U.S. Congressional voting behavior, which reflected a composite of local-lewl sentiments regarding abortion (HSE). These indices reflect the percent of the Senators and Congressmen who voted for restrictive federal funding for medicaid abortions for each state, respectively. In addition to these variables, various measures of distance and contiguity will be developed and used to calibrate several aspects of the spatial constraint dimension. Thus, abortion rate variation for the United States is explained in terms of providers, economics. and sociopolitical considerations, and spatial constraints. The method of analysis
For assessing the annual change in abortion rates a standardized index, &. was developed for each state for each of the four time periods: 1973-1974, 1974-1975, 1975-1976 and 19761977. Using these z-scores, four categories of states were identified based upon their respective scores. These categories were: (1) -9.99 < ditk d - 1.96 significantly lower national rate (Type A) lower (2) - 1.96 < dige C 0.00 negligibly national rate (Type B) (3) 0.00 -Z dig,,< 1.96 negligibly higher national rate (Type C) (4) 1.96 < ditk < 9.99 significantly higher national rate (Type D).
than than than than
To test the assertion that there are regional patterns to abortion a three-stage process was used. First, the data on abortion in the 48 states were standardized and grouped using Wards H Group, a hierarchical classification technique which seeks to maximize between group variation and minimize within group differences [lo]. Three groups of states with ‘similar’ growth profiles in the rates of abortion were identified. Second, the averages for each of these three groups were computed and plotted. Third, a logistic curve was fitted to the average abortion rates. r, for the three groups. Because there will always be an appreciable number of non-adoptors in any state, the hypothesized logistic curve will move toward an asymptote, k, with k less than unity. The equation is r = k/( 1 + e(“-h’)).
(1)
For this study k was set to 0.34, a value slightly higher than the largest average abortion rate for the lead states. It is assumed that the relatively stable abortion rates for these lead states imply that they are ‘close’ to the maximum ratio of abortions per 1000 women 15-44 that will exist in any state under the prevailing socio-economic atmosphere. For any time period the rate of abortion can be computed from (1). dr/dt = hr(l - r/k).
(2)
Previous abortion research has revealed the impact of spatial contiguity on the number of abortion facilities located in an area. Cities located close to New York and Chicago. for example. had more abortionperforming facilities than cities located at great dis-
992
NORAH
F.
HENRY and MILTON E. HARVEY
tames from these two urban centers. In addition, larger urban centers tended to have abortion facilities operational relatively soon after abortion was legalized. Thus, abortion-facility location has been conceptualized as a diffusion process [Z]. Here a similar conceptualization is employed for state abortion rates. That is, those states located distantly from high abortion rate states will tend to have low abortion rates. A regional pattern to abortion rates, then, is discernible with certain high nodes and certain low regions. Testing of the second spatial proposition entails the identification of ‘lead’ nodes and the development of models to capture both distance decay ahd neighborhood effects. While change in abortion rates at these lead states will be minimal, the distance decay hypothesis asserts that the abortion rates of surrounding states will decrease with distance from the lead states. Assuming that there are n such centers, this proposition was tested using the following equation:
In ri, = In (I - bDf + i
C,D,, +
!=1
i
eD,jDf
j=I
(3)
where DC = min Cdl,, 42,
. . .,&Jr
h = the distance from i to lead state j, and a, b, c,,
and ei are parameters. To incorporate the.neighborhood effect into (3), we assume that the abortion rate in a state i will be a function of the abortion rates for the contiguous states. That is ril = f(r,,)
where j = 1,2, . . . , p.
(4)
Because of the variation in p for each of the states, (4) can be modified so that the rate at i is a function of the average in the contiguous states. Thus (4) becOllp3 h
= fk.,).
(9
With this, and introducing the interactive distance decay and contagion, (3) becomes: In rII = In a - bDf + i
j=l
+
w.r
CjDii + i
effects of
While abortion rates increased from 19731977, the annual rate increase in each state generally was not precipitous (see Table 1). The spatial pattern of annual abortion rate changes, illustrated by the respective z-score distributions (see Fig. 4) showed few significant deviations from the national rate of change between any two consecutive time periods, Spatially, those areas having rate increases significantly larger than the national rate of increase were Southern and Plains states. For example, rates of change significantly higher than the national average for 1973-1974 were found for Oklahoma and Utah. For 1974-1975 North Dakota, Louisiana, and Mississippi had significantly higher-than-average growth rates. West Virginia was the lone jurisdiction to exhibit a significant rate of increase between 1975 and 1976. The 19761977 rates of increase for West Virginia, Mississippi, Alabama, and Nevada were significantly greater than the national average. An interesting spatial pattern emerges for those states with abortion rate changes not. significantly greater than the average. With the exception of Maine and Vermont, those states with rates of increase minimally higher than the national average had a tendency to be clustered around the states with significant rate increases. Again, the spatial pattern had a Southern-plains bias. Regionally. then, it is possible to identify Southeastern and Plains as areas where rates of growth of abortion were increasing relatively faster than evident in the rest of the United States (see Fig. 4). While no jurisdiction displayed a rate significantly lower than the national average, those states with less than average rates of increase largely occupied the eastern and western coastal peripheries. The spatial bias evident in the comparison of individual state rate changes with the national rate change, on an annual basis, suggests the importance of distance and spatial contiguity in jurisdictional abortion rates, and the importance of sociopolitical constraints as determinants of abortion. Each of these is addressed below.
i f,D@f’r.r. I=1
Distance and sputial contiguity (6)
Equation (6) was fitted for each of the 5 years, 1973-1977, using a stepwise regression model. In each case the model selected was the last step at which the overall model was significant at the 0.05 level of confidence. Finally, Ordinary Least Squares (OLS) Regression was utilized to explain the integrated socio-politicalspatial dimensions of the state abortion rates for each year of the study. The following general model, derived from the previously described variables, was employed. R = a + b,ERA + b2URB + h,HSE + b$EN +bsPROV
Rate changes and regional patterns
eiDl,Df
i=I +
RESULTS
+ b,COST + b,LV.
(7)
The results of these analyses are presented in the following sections.
A number of observations may be made based upon the H Grouping and logistic curve procedures. discussed earlier. Clearly, the three groups of states have different growth rates (see Fig. 5). Spatially, the three states with consistently high rates are on the east and west coasts (New York, California and Washington). States experiencing early and continuously increasing growth in abortion rates generally were in the interior and also include the larger, more urbanized southern fringe states. The jurisdictions with continuously low abortion rates throughout the study period also were clustered, with several subregions identifiable. The New England Fringe, The Deep South, and The Plains-Rockies-High Plateau are three well-defined areas which emerged with relatively low rates of abortion throughout the study period. An additional, more amorphous region was identified within the eastern interior involving Iowa, Indiana, and West Virginia which had similarly low early rates in comparison with other jurisdications.
Social. spatial and political determinants
of U.S. abortion rates
993
Table 1. Summaries for changes in abortion rates by type Phase
Interval
Type A
Type B
Type C
Type D
1973-1974 1974-197s 197.5-1976 19761977 1973-197s 1974-1976 1975-1977 1973-1976 1974-1977 1973-1977
1 1 1 1 2 2 2 3 3 4
0 0 0 0 0 0 0 0 0 0
41 40 42 27 41 40 42 41 40 41
5 5 5 17 5 5 5 5 5 5
2 3 1 4 2 3 1 2 3 2
The results of the logistic analysis indicate that equation (2) fits the data. For states in the earlier part of the logistic curve the average abortion rate increases for the five time periods are 0.008, 0.0144, 0.0211, 0.0283 and 0.0296, respectively. Although increasing, they are markedly lower than the rate increases for those states in the middle of the adoption curve, with comparable rates of 0.0338, 0.0382, 0.0397, 0.0400 and 0.0351. Notice that the rates first increase, then decrease. In contrast, the rate increases for the
lead states decrease continuously as the asymptote is approached. The values are 0.0213, 0.0123, 0.0113, 0.0113 and 0.0032, respectively (see Fig. 5). An interesting spatial pattern emerges when the states with similar growth profiles are identified on a map. Not only is clear regional identification possible, but also the impact of contiguity and distance, examined via stepwise regression in the following section, are made more visible. Specifically, the lead states of California, Washington, and New York are
1976-77
1975 - 76
Legend 2 - score
9
2yo Miles
,400
0
-9.99
-
-1.96
m
_,,S5
-
0.00
m
0.0, 1.97 Fig.
-
= Significantly = Negligibly
1.96 = Negllglbly 9.99
= Significantly
lower lower
higher
than
than
than
higher
the the
the than
4. Abortion rate changes 1973-1977.
national
nation01
1 type
A)
rate
rate
(type
B)
rate
(type
Cl
nOtiOnal the
nOtiOnOl
rate
( type D)
994
NORAH
,
0.30
- y’
0.25
-
In :
F.
HENRY and MILTON E. HARVEY
I-0
tre
0”
(3.426-0.4711) I *o.s525t 1 1 I I I
I I
I I I
I I
I I I
I 1 1 Q
0.001
1
’
’
2
f
EL L ma,amma
42_
’
”
’
’
r r
--___-__-
’
11 ’
’
kizf 2 P mmmm Time,
AVERAGE
RATES
6 States
in Group in Group in Group
l
e
States States
’
’
FOR :
I (N-3) 2 (N-30) 3 (N-15)
1
’
E 2: 0) EE
t
Fig. 5. Rates of abortion as a function of time (a composite for the three types of states).
contiguous to states in the second category--the middle rate, steeply increasing states. The category three states-low early rates increasing over timeare contiguous to the category two states. These spatial similarities in growth rates are examined mathematically for each year. The result of the regression, presented in the next section, illustrates more clearly the influence of spatial propinquity for each. through time. Distance and contiguity
The stepwise regression results (see Table 2) indicate that important spatial factors-distance decay
and contiguity-are operational. With the exception of 1974. the results show that abortion rates declined with distance from the nearest lead state. In two specific years (1974 and 1977) nearness to one of these lead states had a significant influence on the abortion rates of neighboring states. In 1974 the states around California had relatively higher abortion rates. At the same time, however, those rates declined significantly with distance from the state of California. To a lesser degree, this tendency was replicated in 1977 with Washington State as the lead location. The absence of such a strong regional distance decay effect around New York may
Table 2. Stepwise regression results: relationship between rates of abortion and spatial determinants Independent variables 1. Minimum distance from the closest lead state
1973
1974
-0.0190’ (2.148)
1975
1976
1977
-0.01948 (2.199)
0.009* (2.743)
-0.012* (2.132)
2. Closest to New York 3. Closest to California
0.299* (2.947)
4. Closest to Washington
0.2147* (3.408)
5. Proximity to New York
9. 10. 11. 12.
0.004 (0.565)
- 0.209 (1.784)
6. Proximity to California 7. Proximity to Washington State 8. Average rate in ail continguous
0.0213 (0.749)
0.0297 (1.939)
0.037 (1.319)
0.015 (1.591)
0.023 (1.151)
1.945
1.977 0.479’
2.686 0.438.
2.5601 0.3971
Average rate for states closest to New York Average rate for states closes to California Average rate for states closest to Washington Constant
R’ Values
0.367*
3.159 0.341’
are b-values. Their associated t-values are in parenthesis. Blanks imply the variable did not ‘enter’ the regression.
*Significant at the 0.05 level of confidence.
Social. spatial and political determinants of U.S. abortion rates reflect the fact that such processes may have occurred in the east in 1970-1973. when numerous eastern states were liberalizing their abortion statutes. As this analysis covers the 5 years 1973-1977. this apparent aberration in the system may have been missed. The regional patterns characteristic of abortion rates and relative changes in abortion rates throughout the study period may reflect the cultural, social and political ties between spatially contiguous states. That is, the shared social-cultural-political framework between states which often prompts their regional identification and categorization may contribute to explaining the regional patterns which emerge when examining annual abortion rates. Thus, while the significant b-values indicate that continguity and distance explain an appreciable amount of the variation in abortion rates across states, these distance variables may also reflect important historical sociocultural, political similarities. Socio-political determinants
The variables significant in explaining abortion rates were similar over the study years (see Table 3). Both social and political components were evident. however, neither Senate nor House voting behavior was influential in predicting abortion rates. Neither was the economic variable, mean abortion cost, which was included in the 1976 and 1977 models (the only years for which such data were available) a significant predictor. The effects and significance of the individual predictors varies over the study years. 1973 Abortion rates The analysis reveals that two variables were important in explaining abortion rate variation in 1973 (see Table 3). The percent of women obtaining abortions outside the state of residence and the per capita number of abortion providers in a state were strong predictors of abortion rates. As the number of providers increased the abortion rate increased. An inverse relationship existed between the abortion rate and the percent of women who secured abortions out
Table 3. Sock-political Independent 1.
Annual status of ERA ratification
2. no Leaving state for abortion
3. % Urban 4. Number of providers/l000
women 15-44
5. Senate voting behavior 6. Congressional
of state. As the percent of women securing abortions outside their home states decreased, the abortion rate for the state increased. These variables indicate that a state with comparatively few providers of abortion services and‘a relatively large number of women leaving the state to obtain abortions will have a low abortion rate. Similar results were found for the 1974 state abortion rates. 1974 Abortion rates The results indicate the importance of three variables. Similar to 1973, the percent leaving the state of residence to obtain abortions and the per capita number of abortion ‘providers were important explanatory variables. The percent of the state’s population residing in urban areas also was important in 1974. With a low rate of seeking abortions outside the state of residence and a high per capita number of abortion providers, a state’s abortion rate was higher in 1974. The urban bias characterizing the spread of technological innovation emerged in 1974. High rates of urbanization resulted in higher rates of abortion in 1974. The same variable contributed to explaining the 1975 state abortion rate variation. 1975 Abortion rates The percent of the women securing abortions outside of their home states. the level of urbanization, and the per capita number of providers continued to be important variables in explaining the 1975 abortion rate. The 1975 abortion rate was higher in states where the urbanized population was proportionately larger, where the per capita number of providers was higher and the percentage of women seeking abortion outside the state was low. A discussion of these results is incomplete without mention of the ERA ratification. While not significant at the selected 0.05 level. ratification of the equal rights amendment contributed to the model and should be noted. The results for 1975 are consistent with the 1973 and 1974 results.
determinants
variables
voting behavior
7. The average cost of abortion 8._.Constant R’
F value
*Significant at least at 0.05 level (r-values). NA signifies data not available for inclusion into model
995
of abortion rates: the results 1973 3.18 (1.59) -0.128 ( - 3.70) 0.05 (1.33) 93.14* (2.24) NS -2.11 (70.47) NA
1974
1975
2.08 2.76 (1.31) (1.84) -0.09* -0.012* ( - 2.62) (-3.17) 0.09* 0.09* (2.50) (3.60) 12.19* 8.13* (3.55) (4.04) - 2.08 - 2.77 ( - 1.27) (- 1.09) NA I .22 (0.44) NA NA
8.00
4.23
5.81
0.60
0.66
0.68
12.69*
13.17*
16.84*
1976
1977
3.25* (1.96) -0.12*
0.16 (0.38) -0.07 ( 1.46) 0.18’ (5.38) 8.44” (3.13) 2.30
( -G2’* (3.76) 6.168 (2.35) 0.20 (-0.10) - 2.43 (-0.88) - 0.06 ( - 0.66) 8.61 0.66 1I.038
t 1.24)
0.69 12.61*
NORAH
996 1976
F. HENRYand MILTONE. HARVEY
Abortion rates
For 1976 the result reveals the importance
of Social and political variables in explaining abortion rates. Similar to the 1973-1975 findings, a higher abortion rate in 1976 was attributable to a higher per capita number of providers, a high level of urbanization. a low rate of obtaining abortions outside the home state, and a political variable. Ratification of the ERA was significantly associated with a higher rate of abortion in 1976. 1977 Abortion rules
Unlike the three previous years, in 1977 the variation in abortion rate was attributable to only two variables. Similar to the 1973 results, the degree of urbanization and the provider ratio were the significant predictors of abortion rates. As the level of urbanization and the per capita number of providers increased, a state was more likely to have a higher rate of abortion. These regression results reveal the importance of political dimensions in abortion rates and some underlying spatial, social and political attributes (see Table 3). Between 1973 and 1976 the percent of abortions obtained outside the state of residence was an important explanatory variable in accounting for rate variations. During the entire study period (19731977) the provider ratio also was an important predictor. A large per capita nuniber of abortion providers resulted in a higher rate of abortion. These variables indicate that if abortion facilities exist they will be utilized and if they do not exist in a given locale. they will be found elsewhere. From 1974 to 1977 the level of urbanization in a state was an important predictor of abortion rates. In 1975 a statistically weak interrelationship was found between ratification of the equal rights amendment and a state’s abortion rate. This interrelationship continued to 1976, when ERA ratification was an important explanatory variable. Over time the effects of the individual variables show interesting changes. First, although not statistically significant. the influence of the status of the ERA on abortion rates generally declined (except in 1976) from 1973 to 1977. As more states approved the ERA its effect on abortion decreased. Second, and directly related to the first, is the change in the significance of the percent leaving a state for abortion on abortion rates. By 1977 this was no longer a significant factor. Third, the influence of urbanization on these rates has increased. In fact, the increase in abortion rates with urbanization more than tripled from 1973 to 1977. Fourth, the number of abortion providers per I&MI women 15-44 continued to influence abortion ‘rates significantly. Over time, however, as the number of facilities increased in the states. the rate of abortion increase attributable to this factor declined. SUMMARY
AND CONCLUSIONS
Abortion rates in most states in the U.S. increased following the 1973 Supreme Court decision. A regional pattern to the rate changes emerged with Plains and Southern states having abortion rate
changes significantly higher than the rate increase for the United States as a whole. A distance function was related to these rate changes. Where abortion got an early start, 1970-1973, in some eastern and western states, annual state rate changes were generally less than the national rate increase for the study period. Relatively small increases in abortion rates were visible in states contiguous to these lead states for the 1973-1977 study period, largely because these adjacent states had relatively high abortion rates soon after abortion was legalized. Those states not immediately adjacent to the eastern and western lead states. the Southern and Plain states in this study, experienced relatively low abortion rates and large rate increases for the study period. The abortion rate increase in these three identifiable groups of states, i.e. the lead states, the majority states, and the laggards, conform reasonably well to the logistic curve. Proximity to the lead states had significant influence on abortion rates in adjoining states. This spatial contiguity, reinforced by social. cultural and political history, resulted in regionally discernible abortion rates, explainable by socio-political variables. While certain believable social, spatial and political dimensions to abortion rates for the United States are revealed here, several questions remain. What will be the impact upon abortion rates of the more conservative Congress? Is there spatial similarity to popular attitudes toward abortion? Are these popular attitudes reflected in state abortion rates? Are age-specific state abortion rate variations similar to overall abortion rates? Future researchers into the abortion issue and its spatial dimensions may want to consider these questions. REFERENCES
1.
Forrest J. D.. Sullivan E. and Tietze C. Abortion in the United States, 1977-78. Family 329-341, 1979.
P/am.
Perspcct.
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2. Henry N. F. The diffusion of abortion facilities in the 3. 4.
5. 6. 7. 8. 9.
northeastern United States. 1970-1976. Sot. Sci. Med. ItD, 7-15, 1978. Sullivan E.. Tietze C. and Dryfoos J. G. Legal abortion in the United States. 19751976. Family P/arm. Perspeer. 9, 116-129. 1977. Henry N. F. Responses to a post-abortion questionnaire: spatial. social and contraceptive issues. Unpublished Report Prepared for Planned Parenthood of Broome and Chenango Counties. New York. 1980. Shelton J. D., Brann E. A. and Schulz K. F. Abortion utilization: does travel distance matter? Family Plann. Perspect. 8, 260-262. 1976. Borders J. A. and Cutright P. Community determinants of U.S. legal abortion rates: family Pfunn. Prrspect. Il. 227-233. 1979. Benditt J. Second-trimester abortion in the United States: Special Report in Family Phnn. Prrsprcr. Il. 358-361. 1979. Arney W. R. and Trescher W. H. Trends in attitudes toward abortion. Fumily Plann. Perspect. 8. 117-124. 1976. Callahan D. Abortion and government polity. fami/) Plunn.
Perspect.
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‘IO.Ward J. H. Jr. Hierarchical grouping to optimize an objective function. Am. starisr. Ass. J. 236-244.
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