Experiences of injectable contraceptive users in an urban setting

Experiences of Injectable an Urban Setting

Contraceptive

Users in

HALEH SANGI-HAGHPEYKAR, PhD, ALFRED N. POINDEXTER III, MD, LOUISE BATEMAN, RNC, MPH, AND J. RANDALL DITMORE, MEd Objective: To examine method-related experiences and acceptability of depot medroxyprogesterone acetate (DMPA) among women using this contraceptive for the first time. Methods: Five hundred thirty-six women who received an injection of DMPA from any of seventeen clinical settings in southeast Texas, United States, were followed for 1 year. At each follow-up visit, patients were asked about their experiences with DMPA during the past 3 months and their plans to use this method in the future. Results: Amenorrhea, irregular bleeding, and weight gain were the conditions reported most frequently. Reports of amenorrhea, weight gain, and acne or skin problems increased over time, but complaints of longer periods decreased (P < .OOl). Two pregnancies occurred during the study period. However, of these, one existed before the first injection. Depot medroxyprogesterone acetate’s continuation rate at 1 year was 28.6%. Heavier and more frequent bleeding, increased cramping, amenorrhea, weight gain, headaches, depression, and nervousness were more frequent complaints of women who discontinued DMPA (P < .05), whereas lighter and less frequent bleeding were reported more often by those who continued to use this method (P < .05). Women who discontinued use of DMPA were more likely to be married and have a concern about injectable contraceptives than those who continued to use this method. ConcZusion: Intolerable side effects and changes in menstrual pattern are the most frequently indicated reasons for discontinuing DMPA use. Our results suggest that DMPA’s l-year continuation rate may be lower than previously reported. (Obstet Gynecol 2996;88:227-33)

On October 29, 1992, depot medroxyprogesterone acetate (DMPA), marketed as Depo-Provera (Upjohn, Kalmazoo, MI), became formally approved for use as the first injectable contraceptive by the Food and Drug Administration (FDA). A highly effective contraceptive that is coitus-independent and does not have the limiFrom the Division of Contraceptive Department of Obstetrics and Gynecology, Houston, Texas.

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Research and Development, Baylor College of Medicine,

tation of requiring daily administration, as do oral contraceptives, condoms, and spermicides, may be an attractive alternative for women who may not be using other methods because of this limitation. The availability of this alternative may have profound effects on the occurrence of unintended pregnancies. Despite the numerous advantages of DMPA, it has certain drawbacks. Like other hormonal contraceptives, DMPA use has been associatedwith several side effects, a major one being the disruption of the menses.Change in menstrual pattern is not acceptable to many users and has been reported to be the main reason for discontinuation of DMPA.‘” BecauseDMPA has only recently been approved for use in the United States, all available data on acceptability and experience of side effects has been collected outside the United States’J”-7or before FDA approval.8 However, FDA approval of DMPA and its wider availability may have an influence on acceptability of this injectable contraceptive among family-planning patients. Furthermore, because of cultural differences, opinions and attitudes about DMPA, including satisfaction with the method and reasons for discontinuation, may be different among the American users than among users in other countries. The role of culture on DMPA discontinuation was shown in a World Health Organization (WHO) multicenter study in which the discontinuation rates for prolonged bleeding and amenorrhea among women in Bangkok and Manila were much lower than those for women in Alexandria, Bombay, and Chandigarh.’ The present study was undertaken to examine these issues.The specific aims of the study were 1) to examine the longitudinal changes in bleeding patterns and occurrence of side effects, 2) to determine DMPA’s continuation and failure rates, and 3) to delineate reasons for discontinuation of use. This was done in a prospective, multicenter study of 536 women who received a

0029.7844/96/$15.00 PII SOO29-7844(96)00194-9

227

DMPA proval.

injection

for the first

time after its FDA ap-

Materials and Methods In June 1993, shortly after the FDA approval of DMPA as a contraceptive, 536 women who had decided to use DMPA for the first time were surveyed at 17 provider sites in Texas. The participating clinics consisted of six City of Houston clinics, nine clinics operated by Planned Parenthood of Houston and Southeast Texas, Inc., and two university-based family planning clinics. Before data collection began, the research protocol was approved by the review boards for human research at all participating institutions. After giving informed consent, each subject completed a baseline questionnaire. This questionnaire collected information on the subject’s source of information about DMPA, reasons for selecting this method, concerns about it, and reproductive and contraceptive histories. Demographic information that was available in patients’ charts was abstracted by project staff. The characteristics of the women who received the injection have been shown in detail previously.” However, for the convenience of readers, a brief description of this information is presented here. The ethnic distribution of women who received the injection was 50% black, 25% white, and 25% Hispanic. The women who adopted DMPA ranged in age from 13 to 46 years (mean t standard deviation, 24.4 i 5.7). The mean length of schooling was 11.9 -C 2.9 years. The income level of participants was quite low, because the majority were seen at public clinics serving primarily low-income women. The mean annual income for the entire group was $5978. With respect to reproductive characteristics, the number of pregnancies for the women receiving the injection ranged from zero to ten, with a mean of 1.9 ? 1.6. Number of births ranged from zero to seven, with a mean of 1.2 ? 1.3. One-fourth of the sample women had never been pregnant, and one-third had experienced no births. Furthermore, 32.5% of the women who adopted DMPA reported at least one elective abortion. Women who adopted DMPA were followed for three consecutive injections. At each follow-up, patients were asked about their experience with DMPA during the past 3 months, including any side effects and/or changes in bleeding patterns as well as overall satisfaction with the method, and about plans to use the method for the next 3 months. Receipt of each injection was verified from the subject’s medical records. Satisfaction with DMPA was measured through patients’ responsesto questions about the method’s comfort, convenience, expense, and effect on overall health.

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Answers to these questions could range from 0 to 5. On this scale,a value of 0 indicated extreme dissatisfaction, and 5 meant maximum satisfaction. On each questionnaire, the patients were asked to describe their overall feelings about the decision to use DMPA. This answer also ranged from 0 to 5; 0 meant regretting decision, and 5 indicated feeling most positive about it. Patients who were discontinuing the use of DMPA were also questioned regarding the contraceptive method they were planning to use. The above information was collected from each patient via a self-administered questionnaire upon her return visit to the clinic. A clinic nurse or staff member was available to respond to questions the patients had concerning the questionnaire. When subjects did not return to the clinic, the information was obtained by telephone or mail. Questionnaires were available in both English and Spanish. Procedures for validation of the study questionnaires have been presented previously.” During the study, many women were unable to be assessedfor side effects, bleeding irregularities, extent of satisfaction with DMPA, and future contraceptive plans upon discontinuing the use of DMPA. This category included women who did not complete the follow-up questionnaires at their return visit to the participating clinics and those who could not be contacted by phone or mail. However, to reach a more accurate estimate of DMPA’s continuation rate, the medical records of all study participants, including women who had not completed the follow-up questionnaires, were reviewed for the receipt of each injection. A discontinuer was defined as an individual who, based on medical records, stopped the use of DMPA and switched to another method or to no method. Statistical evaluation comparing groups of interest was performed using analysis of variance, Student t test, g categorical procedure, and life-table analysis. Extent of satisfaction with DMPA was measured using Wilcoxon signed-rank test. Furthermore, changes in reports of side effects and abnormal bleeding patterns over time were examined using categorical data analysis with repeated measures. P 5 .05 was considered significant. All analyses were performed using SAS System statistical software (SAS, Cary, NC).

Results Five hundred thirty-six women who had received DMPA for the first time were followed. A questionnaire administered after 3 months was completed by 463 (86%) of those who received the first injection. Of these, 325 (70%) indicated plans to continue with the method for another 3 months; the remainder were opting to discontinue use of DMPA. Of the women who contin-

Obstetrics & Gynecology

Table

1. Incidence of Side Effects and Abnormal Bleeding Patterns Associated With Use of Depot Medroxyprogesterone Acetate by Months of Injection

ued to use DMPA, 285 (88%) completed the 6-month follow-up questionnaire. Of this group, 226 (79%) said they planned to use this method for another 3 months. Furthermore, of women who indicated plans to continue with the method, 195 (86%) completed the 9-month follow-up questionnaire. Two pregnancies were reported during the course of the study. Of these, based on gestational dates in medical records, one appears to have occurred before the first injection was received. The other occurred in the third month of the first injection’s period. Both pregnancies were terminated by elective abortion and neither woman continued to use DMPA. Omitting the pregnancy that occurred before receiving the first injection, a method failure rate of 0.2 per 100 was estimated using life-table analysis. This failure rate applies to the entire first year of use, becausewomen who received a fourth injection at 9 months were contacted and questioned regarding pregnancies during the 3 months following that injection. Table 1 displays complaints of side effects and abnor-

ma1bleeding patterns associatedwith the use of DMPA at 3,6, and 9 months of use. Weight gain was the most commonly reported side effect, indicated by 38-46% of the DMPA recipients at each follow-up contact. The amount of weight gain by each subject is unknown. Headaches were also a common complaint of DMPA users, reported by nearly one-fifth of the women at each follow-up contact. About one-third of women surveyed reported no side effects associated with the use of DMPA. With respect to changes in bleeding pattern, amenorrhea was the most frequently cited complaint. Other commonly reported changes were spotting or irregular bleeding (40-46%) and longer periods (1926%). Less than 4% of the women using DMPA reported no change in their bleeding patterns. We also investigated longitudinal changes in bleeding patterns and experience of side effects. Reports of weight gain, acne or skin problems, and amenorrhea appeared to significantly increase over time (P < .OOl), but complaints of having longer periods decreased(P < .OOl). With respect to other symptoms, no significant change in the frequency of reporting was seen with repeated injections. Of the original cohort (N = 536), 95% were successfully followed through medical records for the assessment of DMPA’s l-year continuation rate. Twenty-nine women did not return to the participating clinics and were inaccessibleby phone and mail. Three hundred seventy-seven patients discontinued use of DMPA within 1 year after receiving the first injection, resulting in a l-year continuation rate of 28.6% using life-table analyses.The cumulative discontinuation rates were 36.4% after 3 months of use, 54.4% after 6 months, 64.6%after 9 months, and 71.4%after 12 months. Women who discontinued the use of DMPA were compared with those who continued to use this method. No differences were observed in age, ethnic origin, education, number of pregnancies or births, or plans for having children in the future. However, women who used DMPA for the entire study period and at the final survey indicated plans to continue to use this method were more likely to be unmarried (82%) than those who opted to stop use of this contraceptive (66%) (P < .05). Concern about the side effects of DMPA before receiving the first injection was significantly associated with method discontinuation. Women who at 6 months of follow-up indicated plans to continue DMPA use were less likely to have had concerns about the method’s side effects before the first injection than were those who opted to discontinue after 6 months (50 versus 67.3%; 2 = 5.5, P < .05). However, complaints about side effects associated with previous methods were not related to DMPA’s discontinuation.

VOL.

Sangi-Haghpeykar

Symptom

3 months (N = 463)

6 months (N = 285)

9 months (N = 195)

37.6 21.6 13.0 10.4 10.4 8.9 8.6 8.4 7.8 7.3 1.1 14.5 31.5

40.4 16.8 10.5 10.5 11.2 5.6 7.7 5.3 10.5 5.6 2.5 13.0 32.6

45.6 20.0 7.7 7.7 8.7 6.7 7.2 6.2 13.8 2.6 2.6 9.7 29.2

26.1 4.3 46.2

18.6 7.0 42.5

18.5 4.1 39.5

15.3 10.6 46.0 7.1 14.7 7.8 2.6

8.4 10.5 53.3 7.4 16.8 7.0 3.5

6.2 10.8 58.5 6.7 16.4 3.6 2.6

Side effects Weight gain Headaches Nausea Dizziness Hair loss Depression Breast tenderness Vaginal discharge Acne/skin problems Nervousness Facial hair Other* No side effect Abnormal bleeding patterns Longer periods Shorter periods Spotting/irregular bleeding More frequent periods Less frequent periods No periods Heavier bleeding Lighter bleeding Increased cramping No complaints

Numbers represent percentages. Because of multiple responses, numbers add up to more than 100%. * Tiredness, mood swings, low sex drive, weight loss, hot flashes, abdominal pain.

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Table

2. Complaints Discontinue

of Women Who Use at 3, 6, and

Continued 9 Months

to Use Depot of Follow-up

Medroxyprogesterone

3 months % stop (N = 138)

% Continue (N = 226)

31.4

52.2* 29.0+ 17.4

38.1 15.1 10.2

18.5 11.1

Nausea Dizziness Hair

loss

Depression Breast Vaginal

tenderness discharge

Acne/skin Nervousness Facial hair No

side

Shorter Irregular

7% stop

(N = 160)

(N = 35)

50.0 22.4

40.0 17.5

71.4* 31.4

12.1 17.2

6.9 6.3

17.2 8.6

7.5 5.6

8.6 5.2

5.6 5.6

10.3 5.2 0

13.8 1.3 1.9

18.9+

34.4

8.9 9.3

6.5 8.0 8.9

14.5* 10.1

4.9 7.5

7.3 10.1

5.3 10.6

10.9 1.5 23.2’

5.3 3.1 36.3

27.5

17.3

24.1

16.2

2.2 42.0

8.3 44.7

3.5 34.5

5.0 45.0

25.4* 5.1+

6.6 10.6

15.5t

5.6

49.3 8.7

54.4 6.2

8.6 50.0 12.1

12.5 53.8 4.4

8.7’ 7.3

19.0 5.3

6.9’ 13.8%

16.3 3.2

25.5 5.3 44.9 9.9

periods

Less frequent periods No periods Heavier bleeding Lighter Increased

9 months

11.4 14.3 14.3 11.4 14.3 8.6 14.3 8.6’ 5.7 5.T

patterns

periods bleeding frequent

to

X Continue

70 stop (N = 58)

14.5 13.8

0.9 34.2

bleeding periods

Opting

8.6 8.9

6.7 5.9

effects

Abnormal Longer

More

problems

and Those

6 months

7c Continue (N = 325) Side effects Weight gain Headaches

Acetate

12.9 44.6 6.5 17.2

bleeding cramping

7.7

28.6 0 14.3* 8.6 2.9 80.0’ 17.11 17.2 5.7

* P < ,001 +P < .Ol. *P < .05.

Table 2 compares women who ceased to use DMPA with those who continued to use this method with respect to the occurrence of side effects and changes in bleeding patterns. Tables 3 and 4 detail reasons for discontinuing the use of DMPA and future contraceptive choices of the women who stopped using this method. Because this information could be collected only through follow-up questionnaires, the data in Tables 2 through 4 represent patients who completed these questionnaires. In contrast, data concerning the Table

Side effects Change Expensive

in cycle

Want a pregnancy Method too new Did not Other*

specify

3 months

6 months

(N = 138)

(N = 580)

40.6 34.1 1.4

50.0 24.1 1.7

2.2

1.7

1.4 5.9 16.6

1.7 5.2 18.9

Numbers represent percentages. numbers add up to more than 100%.

* Inconvenient, use,

230

concerns

negative about

Sangi-Haghpeykar

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Because

news reports, feeding,

et al

partner

of

doctor

4. Contraceptive Method Depot Medroxyprogesterone

Pill 9 months (N = 35) 42.9 20.2 2.9 5.7 0 8.6 22.9

multiple

responses,

or nurse discouraged

received

Table

Method

3. Reasons for Discontinuation of Depot Medroxyprogesterone Acetate

Reason

l-year continuation rate were obtainable through medical records and were acquired for 95% of the study cohort. Concerning the extent of satisfaction with DMPA, women who stopped using DMPA were significantly less satisfied with the effect of this contraceptive on

vasectomy.

Injectable Contraceptive Users

Condom alone Condom w/foam or cream Cream or foam alone IUD Norplant Sterilization

not

After Discontinuing Acetate

3 months (N = 1381

6 months (N = 58)

9 months (N = 35)

43.4 10.9

34.5 27.6

62.9

2.2 1.5

1.7 1.7

2.2 1.5

1.7 1.7 5.2 22.4

0.7 18.8 9.4

Undecided None Other* Did

Used

13.8

IUD = intrauterine device. Numbers represent percentages. numbers add up to more than 100%. + Includes sponge and withdrawal.

Because

of

8.6

10.3

2.9 2.9

3.4

8.6

1.4 specify

11.4 2.9 5.7

multiple

responses,

Obstetrics & Gynecology

their health, and were more likely to regret having used it, than those who continued to use this method (P -C .OOl). The two groups were similar in other measures of satisfaction, including convenience of the method and its expense. These findings were consistent at 3, 6, and 9 months of follow-up. During the first 3 months of use, reports of weight gain, headaches, and depression were significantly more frequent among women who stopped DMPA use than among those who continued to use it (Table 2). Furthermore, reports of more frequent periods were more common among women who discontinued DMPA use, whereas women who continued to use this contraceptive were more likely to indicate less frequent periods and lighter bleeding. At 6 months of use, women who ceased to use DMPA cited more frequent periods and increased cramping, whereas women who continued to use this method were more likely to report lighter menstrual bleeding. At 9 months of use, weight gain, nervousness, amenorrhea, and heavier bleeding were frequent complaints of women who ended DMPA use, whereas spotting or irregular bleeding were reported more frequently by those who continued to use this method. At each follow-up contact, women who continued to use DMPA were less likely to have experienced any side effects associated with the use of DMPA compared with those who discontinued use (Table 2). An average of 1.6 side effects were reported by women who continued to use DMPA after 3 months of use, compared with 2.3 for those who stopped its use at this time (P < .OOl). At 6 months, an average of 1.6 side effects were reported by women continuing to use DMPA, compared with 2.1 by those stopping its use (P < .05). At 9 months of use, the average number of side effects reported by the two groups were 1.6 and 2.4, respectively (P < .05). Reasons specified for discontinuing use of DMPA are listed in Table 3. The most frequently reported reasons were intolerable side effects, followed by changes in menstrual bleeding. Between 2 and 6% of the women who terminated DMPA use did so because they wanted a child. Reasons for discontinuing DMPA use were examined with respect to demographic characteristics and reproductive histories. White women and those with a higher number of previous pregnancies were significantly more likely to stop use of DMPA because of its side effects than were blacks and Hispanics or women with fewer previous pregnancies (P < .05). Age, education, marital status or change in marital status, and number of live births were unrelated to the type of reason indicated by women for discontinuing the use of DMPA. Women who ceased to use DMPA were questioned regarding the contraceptive method they planned to

The present study is the first reported investigation in the United States to examine method-related experiences and acceptability of DMPA since its FDA approval as a contraceptive. Reporting of side effects and menstrual alterations in this study was similar to patterns reported in the world literature.‘,4-6 The most common side effects were weight gain and headaches, and the most frequently reported changes in bleeding pattern were amenorrhea and irregular bleeding. Menstrual changes occurred with greater frequency than nonmenstrual side effects. This pattern is in contrast to studies conducted among Norplant (Wyeth-Ayerst, Philadelphia, PA) patients, in which reports of nonmenstrual side effects were somewhat higher than complaints of abnormal bleeding.“-I3 With respect to the method’s failure rate, the firstyear pregnancy rate of 0.2% observed in this investigation compares favorably with studies of DMPA conducted in other countries?Y investigations conducted in the United States before DMPA’s FDA approval,” and studies conducted with Norplant, another long-acting progestin.“,r4 Concerns about the potential side effects associated with the use of contraceptives and the actual experience of side effects are the primary reasons for switching from one method to another, or to no method, among women at risk for unintended pregnancies.15 Consistent with these reports, we found that concerns about DMPA’s side effects before the first injection were associated with DMPA acceptability. Furthermore, the effects of this contraceptive on health and bleeding patterns were the primary reasons for method discontinuation. Although abnormal bleeding patterns and other side effects were present both among women who stopped use of this method and among those who continued to use it, they were more prevalent among the former group. Weight gain, headaches, depression, nervousness, heavier bleeding, more frequent periods, increased cramping, and amenorrhea were reasons cited for stopping the use of DMPA, whereas lighter bleeding and less frequent periods were indicated more by those who continued to use it. Change in menstrual pattern, in particular amenorrhea, was also the main reason for DMPA discontinuation in studies of DMPA acceptability conducted in other countries.‘”

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use instead of DMPA (Table 4). Oral contraceptives were the most commonly selected method, followed by condoms. Between 3 and 10% of the women who ended DMPA use were not planning to use a contraceptive method, and nearly one-fifth were undecided. The remainder planned to use a variety of other methods.

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Marital status was also associated with DMPA acceptability. A significantly higher proportion of women who continued use of DMPA were unmarried compared with those who stopped use of this method. Acceptability and continued use of DMPA, a contraceptive whose effectiveness is not user-dependent, among unmarried women, may have profound implications for the occurrence of unintended pregnancies. Such pregnancies have been reported to be highest among teens, minorities, and unmarried women.‘6-18 Concerning changes in bleeding patterns over time, polymenorrhea and prolonged bleeding and spotting have been reported to be more frequent after the first injection and are gradually replaced by longer cycles, less bleeding, and total amenorrhea after repeated injections.3z6 Consistent with these reports, we found a significant increasein the reports of amenorrhea among subjects who received repeated injections, whereas reports of longer periods decreased with duration of use. Because amenorrhea is not acceptable to many users and appears to be a reason for method discontinuation,‘” more women may be expected to stop use of DMPA with repeated injections. Nonmenstrual complaints that increased with continued use were weight gain and acne or skin problems. Increase in body weight with repeated injections was also seenin a study of DMPA use conducted on Egyptian women, although the increase was not statistically significant.’ However, in that study, weight gain was welcomed by the particiuants and was not a reason for method discontinuation. Unlike in the developing countries, obesity is not acceptable to women in the developed world.” Weight gain was a cause of DMPA discontinuation in the present investigation. The l-year continuation rate of DMPA observed in the present study was 28.6%. This rate is considerably lower than method continuation rates reported in other countries,‘-3’9’20 the rate observed among American users before the FDA approval of DMPA as a contraceptive,’ and rates among Norplant accepters in a similar patient population.” Slightly lower rates (2526.9%) were shown in three centers in a WHO multicenter study,3 although these rates were based on small numbers. The reasonsspecified by patients for stopping the use of DMPA indicate that certain aspects of this injectable contraceptive appear to be intolerable and lead to discontinuation. Careful patient education and counseling can minimize the use of DMPA in inappropriate candidates, such as women unwilling to tolerate menstrual changes, headaches, or weight increases. Information about DMPA should include a detailed description of all the side effects that are likely to occur. Such knowledge may help women select a contraceptive that is appropriate for their needs and concerns, I

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leading to less contraceptive switching, which has been reported to increase the risk of unintended pregnancies.*’ The majority of the patients in the present study were indigent, although there was an adequate representation of each ethnic group in our sample. Unless one can argue that indigent women are physiologically different from their more affluent counterparts, our findings on the occurrence of side effects and menstrual alterations can be generalized to the entire population of DMPA users. However, women who are of lower socioeconomic status may be different from those who are not economically disadvantaged with respect to method acceptability. Future studies investigating DMPA’s continuation rates and reasons for discontinuation among women of higher socioeconomic status are needed in order to understand the broader impact of this injectable contraceptive on the reproductive health of American women.

References 1. Salem HT, Salah M, Aly MY, Thabet AI, Shaaban MM, Fathalla MF. Acceptability of injectable contraceptives in Assiut, Egypt. Contraception 1988;38:697-710. 2. Gray RH, Parker RA, Diethelm I’. Vaginal bleeding disturbances associated with the discontinuation of long-acting injectable contraceptives. Br J Obstet Gynaecol 1981;88:317-21. 3. WHO Special Programme of Research, Development, and Research Training in Human Reproduction; Task Force on LongActing Agents for the Regulation of Fertility. Multinational comparative clinical trial of long-acting injectable contraceptives: Norethisterone enanthate given in two dosage regimens and depot-medroxyprogesterone acetate. Final report. Contraception

1983:28:1-20. 4. Fraser IS, Dennerstein GJ. Depo-Provera use in an Australian metropolitan practice. Med J Aust 1994;160:553-6. 5. Jarman H, Kovacs GT, Westcott M. Depo-Provera: A profile of current users. Aust N Z J Obstet Gynaecol 1990;30:74-6. 6. WHO Special Programme of Research, Development, and Research Training in Human Reproduction; Task Force on LongActing Agents for the Regulation of Fertility. Multinational comparative clinical evaluation of two long-acting injectable contraceptive steroids: Norethisterone enanthate and medroxyprogesterone acetate. 2. Bleeding patterns and side effects. Contraception 1978;17:395-406. 7. WHO Special Programme of Research, Development, and Research Training in Human Reproduction; Task Force on LongActing Agents for the Regulation of Fertility. A multicentered phase III comparative clinical trial of depot-medroxyprogesterone acetate given three-monthly at doses of 1OOmg or 150mg. II. The comparison of bleeding patterns. Contraception 1987;35:591-610. 8. Schwallie PC, Assenzo R. Contraceptive us-Efficacy study utilizing medroxyprogesterone acetate administered as an intramuscular injection once every 90 days. Fertil Steril 1973;24:331-9. 9. WHO Special Programme of Research, Development, and Research Training in Human Reproduction; Task Force on LongActing Agents for the Regulation of Fertility. Multinational comparative clinical evaluation of two long-acting injectable contraceptive steroids: Norethisterone oenanthate and medroxy-

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19. Sobal J, Stunkard AJ. Socioeconomic status and obesity: A review of the literature. Psycho1 Bull 1989;105:260-75. 20. Fakeye 0. Contraception with subdermal levonorgestrel implants as an alternative to surgical contraception at Ilorin, Nigeria. Int J Gynaecol Obstet 1991;35:331-6. 21 Grady WR, Hayward MD, Billy JO, Florey FA. Contraceptive switching among currently married women in the United States. J Biosoc Sci 1989;11:117-32.

Address

reprint

requests

to:

Halek San&Hagkpeykar, PkD Department of Obstetrics and Gynecology Baylor College of Medicine One Baylor Plaza Houston, TX 77030

Received November 27, 1995. Received in revised form April 3, 1996. Accepted April 8, 1996.

Copyright 0 1996 by The American College of Obstetricians Gynecologists. Published by Elsevier Science Inc.

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