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Reproductive health history of lesbians: implications for care
American Journal of Obstetrics and Gynecology (2004) 190, 1298e304
www.elsevier.com/locate/ajog
Reproductive health history of lesbians: Implications for care Jeanne M. Marrazzo, MD, MPH,* Kathleen Stine, NP Department of Medicine, University of Washington, Seattle, Wash Received for publication June 18, 2003; revised December 4, 2003; accepted December 4, 2003
–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– KEY WORDS Lesbian Pregnancy Abortion Bisexuality
Objective: Parity and hormonal contraceptives modify the risk of reproductive cancers and cardiovascular disease. However, clinicians may not obtain reproductive histories from patients who self-identify as lesbian. We report lifetime pregnancy-related outcomes and hormonal contraception for 392 women who reported sexual activity with another woman in the preceding year. Study design: Among self-referred volunteers, previous pregnancy, pregnancy outcome, contraceptive use, and sexual identity were assessed with self-administered questionnaire. Results: One in 4 subjects had been pregnant, and more than 50% of the women had used oral contraceptives (mean duration, 40 months). Sixteen percent of all subjects and 63% of those who had been pregnant previously reported having 1 or more induced abortions. The most common pregnancy outcome for women younger than 25 years was induced abortion (59% of pregnancies). Identifying as ‘‘lesbian’’ or ‘‘bisexual’’ predicted neither the duration of oral contraceptive use nor a report of induced abortion. Conclusion: Previous pregnancy, induced abortion, and hormonal contraceptive use are common among women who report sex with women, regardless of self-identification as lesbian. Ó 2004 Elsevier Inc. All rights reserved.
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– Although estimates of lifetime same sex behavior vary, 1.4% to 5% of all women may be sexually active with other women.1 In the United States, an estimated 2.3 million women describe themselves (self-identify) as lesbian.2 Although numerous studies have reported that most women who self-identify as lesbians (53%-99%) have had sex with men and many of these women
Supported by a National Institutes of Health grant (R29-AI4115304). * Reprint requests: Jeanne M. Marrazzo, MD, MPH, Harborview Medical Center, Division of Infectious Diseases, 325 9th Ave, Mailbox #359931, Seattle, WA 98104. E-mail: [email protected] 0002-9378/$ - see front matter Ó 2004 Elsevier Inc. All rights reserved. doi:10.1016/j.ajog.2003.12.001
(21%-30%) continue to have sex with men,3 scant data are available on the reproductive history, including pregnancy and hormonal contraceptive use, of this group. Until recently, the major ‘‘women’s health’’ studies did not collect information on same-sex behavior or sexual identity. Because parity and hormonal contraceptive use modify the risk of important health outcomes (which include cardiovascular disease and breast, ovarian, and cervical cancers4-7) and because controversy exists about some aspects of the implementation of screening protocols, particularly for mammography, it is important that women’s health care providers routinely assess these parameters. Further, a history of pregnancy that results in abortion may indicate risk behavior that
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Marrazzo and Stine is associated with the acquisition of sexually transmitted diseases (STDs) that can affect a woman’s future reproductive health.8 However, lesbian patients may not receive appropriate assessment of these exposures and outcomes routinely or, particularly in the case of Papanicolaou test screening for cervical cancer, the screening interventions that are prompted by their report.9-12 In fact, routine Papanicolaou test screening is performed less frequently among lesbians than national guidelines advise,10,13,14 although sexual transmission of oncogenic genital human papillomavirus (HPV) has been reported to occur between women,10,14,15 and genital HPV may be detected in up to 40% of lesbians.14 We examined self-report of previous pregnancy, pregnancy outcome, and hormonal contraceptive use in a group of women who reported sex with another woman in the previous year and who were enrolled in a community-based study of STDs and cervical neoplasia. Of specific interest was the outcome of induced abortion, which is often an indicator of unintended pregnancy in young adult and adolescent women. For the remainder of this report, we define ‘‘lesbian’’ using the dimension of same-gender sexual behavior, as did Laumann et al.1 However, we also asked women to provide their self-defined sexual identity, which included the term lesbian as an option; we specify the use of this term as such when discussing these results.
Material and methods Women were recruited from February 1998 through December 2001 through advertisements that were posted in community venues (restaurants, bookstores, clubs, and bars), newspaper and magazine articles, and referral from community clinics. Because self-identifying as lesbian may not predict actual participation in same-sex behavior or its frequency, we oriented recruitment materials to women who had sex with other women, regardless of self-identification. However, we also asked women to define themselves as ‘‘lesbian,’’ ‘‘bisexual,’’ or ‘‘straight.’’ Women were eligible for enrollment if they were between the ages of 16 and 45 years, could provide written informed consent, and reported having sex with another woman in the preceding year. The timeframe of 1 year for sexual exposure to female partners was chosen because we also assessed risk of genital HPV acquisition from female partners, as previously described.10,14 Sexual behavior with either male or female partners was defined as contact between oral and/or genital mucosa to genital mucosa. When participants phoned to make an appointment, they received by mail an extensive standardized questionnaire that detailed demographic characteristics and medical, reproductive, and sexual history, which they
completed and brought to their appointment. The questionnaire specifically included information on insurance status, cigarette and alcohol use, the number of previous pregnancies, age at pregnancy, pregnancy outcome, douching history, types of hormonal contraceptive and dates of use, Papanicolaou test history, self-reported history of STD, current genital symptoms, number of lifetime male and female sex partners, and sexual behaviors. Women were asked to define themselves as ‘‘lesbian,’’ ‘‘bisexual,’’ or ‘‘straight.’’ The questionnaire was reviewed for completion with the subject by the research clinician (K.S.) or principal investigator (J.M.M.). Concomitant clinical assessment included a pelvic examination with testing for genital HPV by polymerase chain reaction, assessment of vaginal bacteria, and Papanicolaou cervical cytologic condition, as reported previously.10,16 Statistical analysis was performed using SPSS software (SPSS Inc, Chicago, Ill). Direct comparisons of proportions were made using Pearson’s chi-squared test. Continuous variables were compared with the use of the Student t test or the Mann-Whitney test for nonparametric data. Multivariate analysis was performed by logistic regression techniques. For all variables in the multivariate analysis, data that were missing were categorized as ‘‘missing’’ and included in the analysis. Because subjects were not asked specifically whether each pregnancy was intended, the primary outcome for the multivariate analysis was the report of induced abortion, a reasonable surrogate for unintended pregnancy. Tests of significance were 2-tailed and used a significance level of a probability value of !.05. The study’s procedures were approved at the onset and reviewed annually by the University of Washington Human Subjects Research Review Committee.
Results A total of 392 women were recruited, most of whom responded to posted advertisements in community venues or who were referred by a friend or partner (Table I). The women were predominantly white, relatively highly educated, and !30 years old (median age, 28 years). Although mean income was relatively high, 31% of the women reported having no current health insurance coverage. Most women (89%) reported no current genitourinary symptoms; the remainder of the women reported abnormal or increased vaginal discharge or itching. Although most women (66%) self-identified as lesbian, 80% of the women also reported having had intercourse with a male partner during their lifetime, and 28% of the women reported doing so in the previous year. Of the 257 women who self-identified as lesbian, 187 women (73%) had ever had sex with a man, and 22 women (8.6%) had done so in the previous year.
1300 Table I
Marrazzo and Stine Characteristics of study subjects (n = 392 women)
Characteristic Age (median, 28 y; range, 17-56 y) !25 y 25-30 y 31-39 y O39 y Race White Black Asian/Pacific Island Native American Other Hispanic* Current health insurance Monthly individual income (mean, $1870; range, 0-$7200) !$1800 O$1800 Not reported Marital status Never married to a man Divorced Ever married, not divorced Educational level High school diploma Some college College degree or higher Previous pregnancy Hormonal contraceptive use Current Ever (includes current) Before 1975 Never Male partners Sex with male, ever Sex with male, previous year Lifetime male partners (median) Lifetime female partners (median) Recruitment sourcey Posted advertisements/article Clinic referral Friend or partner
Subjects (n) 119 113 100 60
(30%) (29%) (26%) (16%)
344 7 13 8 20 21 270
(88%) (1.8%) (3.4%) (2.0%) (5.2%) (5.4%) (69%)
194 (49%) 154 (39%) 44 (12%) 337 (86%) 43 (11%) 12 (3.1%) 16 137 239 97
(4.2%) (35%) (61%) (25%)
24 206 23 176
(6.1%) (53%) (5.9%) (45%)
313 (80%) 110 (28%) 7 6 86 (41%) 21 (10%) 100 (48%)
* Eight of the 21 women who reported Hispanic ethnicity reported no race category in addition to ethnicity. y Two hundred nine women were specifically queried after the questionnaire was modified to include this information; percentages refer to this denominator.
The number of lifetime male partners did not differ between women who identified as lesbian and women who identified as bisexual (P=.12). Among all subjects, 97 women (25%) had been pregnant at least once, and more than one half of the women had used oral contraceptives at some point during their lifetime. Sixty-one women reported having had R1 abortions (16% of all subjects; 20% of those who had ever had sex with a man; and 63% of those who had ever been
pregnant). Pregnancy outcomes and hormonal contraceptive use history are stratified by demographic characteristics, sexual history, and self-defined sexual identity in Table II. Not surprisingly, the report of these outcomes increased with the increasing age of subjects, with more than one half of all women R40 years old reporting a previous pregnancy or ever having used oral contraceptives. There were no differences in reported frequency of these outcomes when women were stratified by educational level or current income. Women who self-identified as bisexual were more likely to report a previous pregnancy or ever having used oral contraceptives; however, neither the prevalence of the report of previous abortion nor the duration of oral contraceptive use significantly differed between women who identified as lesbian compared with those who identified as bisexual. Finally, all 3 outcomes (pregnancy, abortion, and oral contraceptive use) were associated strongly with a reported increasing number of lifetime male sex partners. Of the 206 women who reported having used oral contraceptives, information on type and duration was available for 182 women (88%). Mean duration of use was 40 months (range, 1- 192 months). Twenty-five women (6% of all subjects, and 20% of subjects over 35 years old) used oral contraceptives before 1975. Two women reported the use of a low-dose estrogen compound and a progesterone-only compound, respectively; most of the remaining women did not recall the specific type. However, most preparations that were available before 1975 contained relatively high concentrations of ethynyl estradiol (R50 mg/mL). One of these 23 women reported a history of breast cancer, and 10 women (43%) reported that a family member had had breast cancer (first-degree relative in 4 women [17%] and second-degree in 7 women [30%]). Seventeen of these 23 women (74%) reported their self-identity as lesbian. Table III shows the risk factors for the report of a history of induced abortion among subjects who reported ever having had sex with a man (n = 313 women). Significant associations were seen in univariate analysis for age at first pregnancy of 20 to 24 years, age at first sex with male partner of %17 years, and increasing number of lifetime male partners. In the multivariate model, however, only increasing number of lifetime male partners remained associated significantly with this outcome (adjusted odds ratio for women who reported R8 male partners relative to those reporting %4 male partners, 6.9; P = .05). Although younger age at first sex with a female partner and current lower median income were associated with an increased likelihood of report of induced abortion, these associations were not statistically significant (P = 0.4 for both). As shown in Figure, the 97 women who reported ever having been pregnant experienced 176 obstetric outcomes, including live birth in 20 women (21%), induced abortion in 28 women (29%), and fetal loss in
1301
Marrazzo and Stine 17 women (18%). One woman reported a molar pregnancy, and 1 woman reported an ectopic pregnancy. Most pregnancies occurred when the women were in their third decade (20-29 years old), but 1 in 4 pregnancies (26%) occurred during adolescence. The most common pregnancy outcome for women younger than 25 years of age was induced abortion, which occurred in 59% of all pregnancies in this age group. Among women who reported a history of induced abortion, the median number of these events was 1 (range, 1-4 events).
Comment Among women reporting sex with another woman in the previous year, most of whom self-identified as lesbian, lifetime reports of previous pregnancy, oral contraceptive use, and induced abortion were common. Overall, 25% of women had been pregnant at least once, and 16% had had an abortion. Most women (63%) who had ever been pregnant had had at least 1 abortion. One fifth of the subjects who specifically self-identified as lesbian had been pregnant at least once; 12% of them had had an induced abortion, and almost one half of them had ever used oral contraceptives. Of related importance, the number of reported lifetime male sex partners did not differ by whether women identified as lesbian or bisexual. Because these findings demonstrate that self-identification as lesbian does not preclude the previous use of oral contraceptives or pregnancy-related outcomes consistently, providers must address these issues with all adult women patients, regardless of stated sexual identity or behavior. These findings may be particularly important for clinics with a traditional family planning focus, because these may serve as the primary entry point of care for many lesbians, particularly those with limited resources. Further, our results suggest that inclusion of some measure of same-sex behavior is warranted even in surveys that have traditionally focused on reproductive health outcomes of women who were assumed to have heterosexual experience exclusively. Our findings generally agree with those of the few published studies that have reported on reproductive outcomes among lesbians. Only 1 recent large-scale study that included pregnancy and hormonal contraceptive use history reported results that were stratified for respondents’ same-sex behavior.11 Among participants in the Women’s Health Initiative, ever use of oral contraceptives was similar between lesbians and heterosexual women, and 35% of the women reported ever having been pregnant.11 Among 2356 women who were surveyed in 1980, 48% of 1921 self-identified lesbians reported ever using oral contraceptives, and 13% of them reported ever using an intrauterine device; 23% of these
Table II Pregnancy outcomes and hormonal contraceptive use by demographic characteristics and self-reported sexual identity*,y
Characteristic Current age !25 25-39 R40 P (trend)* Education %High school + some college RCollege degree P* Race White Nonwhite P* Current monthly household income !$1800 O$1800 P* Self-defined sexual identity Lesbian Bisexual P* Lifetime male sex partners %3 4-7 8-15 R16 P (trend)*
Hormonal Previous Abortion contraceptive pregnancy (n) history (n ) use ever (n) 10 (8.4%) 53 (25%) 34 (57%) !.001
8 (6.7%) 37 (18%) 16 (27%) NS
52 (44%) 112 (53%) 38 (63%) !.02
49 (32%)
28 (18%)
76 (50%)
48 (21%) .16
33 (14%) .29
126 (54%) .52
81 (24%) 16 (34%) .15
53 (15%) 8 (17%) .27
181 (53%) 21 (45%) .34
43 (22%) 45 (30%) .13
27 (14%) 30 (20%) .66
90 (47%) 83 (55%) .15
52 (21%) 44 (34%) .006
31 (12%) 30 (23%) .5
113 (45%) 87 (68%) !.001
7 (7.6%) 18 (24%) 25 (35%) 45 (59%) !.001
2 (2.2%) 9 (12%) 19 (27%) 30 (39%) .06
36 (39%) 52 (70%) 47 (66%) 60 (79%) !.001
* Percentages refer to the proportion of women who experienced the outcome relative to all women in a given category (for example, 7.8% of women who were !25 years old and who reported a previous pregnancy). y The level of significance of differences within demographic categories for each of the outcome variables (for example, increasing age that is associated significantly with the outcome of previous pregnancy [P !.001 for trend], but the current household income was not [P = .13]).
women had ever been pregnant, with 53% reporting elective abortion and 20% reporting spontaneous abortion.17 As recently reported for another communitybased sample of lesbians,18 our subjects reported a lower prevalence of parity than that of women in the United States in general. However, relative to data for women in the United States reported in the National Survey of Family Growth, our subjects had a comparable estimated rate of induced abortions.19
1302 Table III
Marrazzo and Stine Risk factors for report of previous abortion among subjects with a history of sex with men (n = 313 women)*
Characteristic Age at first pregnancy %19 y 20-24 y R25 y Race Nonwhite White Education %High school + some college RCollege degree Self-defined history of problem drinking Income (monthly) !$1800 O$1800 Age at first sex with male partner %17 y R17 y Age at first sex with female partner %20 y R20 y Lifetime male sex partners (n) %3 4-7 R8
Subjects (n)
Univariate odds ratio (95% CI)
P value
Multivariate odds ratio (95% CI)
P value
39 31 25
1.9 (0.7, 5.4) 3.7 (1.2, 12) Referent
.5 .03
3.1 (0.8, 10) 2.9 (0.8, 12) Referent
.11 .11
34 272
1.2 (0.6, 3.0) Referent
.5
0.3 (0.1, 1.2)
.2
127 186 67
1.2 (0.8, 1.9) Referent 1.0 (0.6, 1.7)
.3
.4
.9
0.6 (0.2, 1.8) Referent 0.5 (0.1, 1.6)
121 157
1.6 (0.9, 2.8) Referent
.7
1.6 (0.5, 4.6)
.4
167 139
1.7 (1.0, 1.4) Referent
.04
0.7 (0.2, 2.2)
.5
165 147
0.6 (0.3, 1.1) Referent
.08
1.2 (0.4, 3.8) Referent
.4
92 74 147
Referent 6.2 (1.3, 30) 23 (5.6, 98)
.02 !.001
Referent 1.6 (0.2, 12) 6.9 (1.0, 46)
.4
.7 .05
* Numbers in columns may not add to 313, because information on some characteristics was not available for all subjects.
Figure Pregnancy outcomes among 97 women by age at event (total events = 176 [does not include 1 episode each of ectopic pregnancy and molar pregnancy]). The open portion of the bars represents induced abortion; the gray portion of the bars represents fetal loss; and the closed portion of the bars represents live birth.
Beyond the assessment of reproductive health history, our findings emphasize that self-identification as lesbian should not preclude the performance of a complete sexual health history. Lesbians who are also currently sexually active with men may demonstrate increased sexual risk-taking behavior in some settings, which is a finding that is supported by the high proportion of pregnancies that ended in abortion. Among
women who attended STD clinics, the report of sex with women in addition to sex with men has been associated with a high prevalence of human immunodeficiency viruserelated risk behaviors, including sex with gay or bisexual men, the use of injection drugs, the use of crack cocaine, and the exchange of sex for drugs or money.20,21 In the 1997 College Alcohol Study, comprised of 14,251 randomly selected US college students, women who reported sex with both men and women were more likely to report multiple sex partners than peers with only opposite-sex partners.22 Despite these findings, several factors may contribute to lesbians not receiving thorough evaluation for reproductive health.11,23 First, some evidence suggests that providers may assume that because a woman self-identifies as lesbian, sexual and reproductive histories are of relatively little import. 10 Most studies of preventive screening that is related to these assessments have focused on lesbians’ experience with Papanicolaou tests, which may be a reasonable surrogate for reproductive health assessment and screening. As previously reported, our subjects reported being told they did not need Papanicolaou tests because they were lesbians; the provider was a physician in 90% of these events.10 Second, lack of medical insurance may contribute; despite the report of relatively high income among our subjects,
1303
Marrazzo and Stine almost one third of them did not have health insurance. Third, some studies have noted that most lesbians (53%72%) do not disclose their sexual behavior to physicians when they seek medical care.24 In a survey of 6935 selfidentified lesbians, disclosure of sexual orientation was associated favorably with the receipt of appropriate Papanicolaou test screening.9 Finally, lesbians who do not have sex with men are not likely to access venues that provide reproductive health care for the sole purpose of obtaining birth control, which effectively eliminates another ‘‘routine’’ opportunity for assessment and screening. Our study has important limitations. First, subjects were self-referred, and may not be representative of all lesbians. Specifically, women who self-refer to studies that recruit on the basis of clearly-stated ‘‘sexual minority’’ behavior conceivably could be biased towards the inclusion of women who are more comfortable discussing their current and past sexual and pregnancy history. This could bias estimates for outcomes (such as induced abortion upwards) that are relative to those estimates that are derived from a population-based survey. However, population-based sampling methods do not generate reliably substantial, and possibly diverse, representation of populations that may be less visible because of minority status (such as sexual orientation).25 Second, most of our subjects were white. Because disparities in health care seeking and risk behavior among lesbians may be modified by race,12 a more comprehensive study of racially diverse groups of lesbians is needed. Third, our sample size may have been too small to detect statistical significance for several associations. Finally, we did not ask subjects specifically whether each pregnancy was intended, nor did we assess specific reasons for the use hormonal contraceptives; subjects may have used them for indications unrelated to contraception. Erroneous assumptions about the reproductive history of lesbians may place them at increased risk for delayed detection of adverse outcomes. Specifically, a provider’s knowledge of a lesbian’s reproductive history can help to inform counseling about preventive behaviors, individual decisions about screening, and risk for outcomes for diseases other than STDs, including breast and cervical cancers. Our findings support the need for an investigation in a larger number of women. Such information will help to clarify messages that are provided to lesbians about their risk of outcomes that are related to these factors and should direct efforts to educate providers about the appropriate care and counseling of lesbians.
Acknowledgments We thank Laura Koutsky for general support of this study and Alison Starling for assistance with data management.
References 1. Laumann O, Gagnon JH, Michael RT, Michael S. The social organization of sexuality: sexual practices in the United States. Chicago: University of Chicago Press; 1994. 2. Lesbian health: current assessment and directions for the future. Washington (DC): Institute of Medicine; 1999. 3. Diamant AL, Schuster MA, McGuigan K, Lever J. Lesbians’ sexual history with men: implications for taking a sexual history. Arch Intern Med 1999;159:2730-6. 4. Grabrick D, Hartmann LC, Cerhan JR, Vierkant RA, Therneau TM, Vachon CM, et al. Risk of breast cancer with oral contraceptive use in women with a family history of breast cancer. JAMA 2000; 284:1791-8. 5. Tanis B, van den Bosch MA, Kemmeren JM, Cats VM, Helmerhorst FM, Algra A, et al. Oral contraceptives and the risk of myocardial infarction. N Engl J Med 2001;345:1787-93. 6. Whittemore AS, Harris R, Itnyre J. Characteristics relating to ovarian cancer risk: collaborative analysis of 12 US case-control studies: IV, the pathogenesis of epithelial ovarian cancer: Collaborative Ovarian Cancer Group. Am J Epidemiol 1992;136:1212-20. 7. Moreno V, Bosch FX, Munoz N, Meijer CJ, Shah KV, Walboomers JM, et al. Effect of oral contraceptives on risk of cervical cancer in women with human papillomavirus infection: the IARC multicentric case-control study. Lancet 2002;359:1085-92. 8. Henshaw SK, Kost K. Abortion patients in 1994-1995: characteristics and contraceptive use. Fam Plan Perspect 1996;28:140-7 158. 9. Diamant AL, Schuster MA, Lever J. Receipt of preventive health care services by lesbians. Am J Prev Med 2000;19:141-8. 10. Marrazzo JM, Koutsky LA, Kiviat NB, Kuypers JM, Stine K. Papanicolaou test screening and prevalence of genital human papillomavirus among women who have sex with women. Am J Public Health 2001;91:947-52. 11. Valanis BG, Bowen DJ, Bassford T, Whitlock E, Charney P, Carter RA. Sexual orientation and health: comparisons in the women’s health initiative sample. Arch Fam Med 2000;9:843-53. 12. Mays VM, Yancey AK, Cochran SD, Weber M, Fielding JE. Heterogeneity of health disparities among African American, Hispanic, and Asian American women: unrecognized influences of sexual orientation. Am J Public Health 2002;92:632-9. 13. Rankow EJ, Tessaro I. Cervical cancer risk and Papanicolaou screening in a sample of lesbian and bisexual women. J Fam Pract 1998;46:139-43. 14. Marrazzo JM, Koutsky LA, Stine KL, Kuypers JM, Grubert TA, Galloway DA, et al. Genital human papillomavirus infection in women who have sex with women. J Infect Dis 1998;178: 1604-9. 15. O’Hanlan KA, Crum CP. Human papillomavirus-associated cervical intraepithelial neoplasia following exclusive lesbian sex. Obstet Gynecol 1996;88:702-3. 16. Marrazzo JM, Koutsky LA, Eschenbach DA, Agnew K, Stine K, Hillier SL. Characterization of vaginal flora and bacterial vaginosis in women who have sex with women. J Infect Dis 2002;185: 1307-13. 17. Johnson SR, Smith EM, Guenther SM. Comparison of gynecologic health care problems between lesbians and bisexual women: a survey of 2,345 women. J Reprod Med 1987;32:805-11. 18. Dibble SL, Roberts SA, Robertson PA, Paul SM. Risk factors for ovarian cancer: lesbian and heterosexual women. Oncol Nurs Forum 2002;29:E1-E7. 19. Ventura SJ, Mosher WD, Curtin SC, Abma JC, Henshaw S. Trends in pregnancies and pregnancy rates by outcome: estimates for the United States, 1976-96: National Center for Health Statistics. Vital Health Stat 2000;21:1-47. 20. Bevier PJ, Chiasson MA, Heffernan RT, Castro KG. Women at a clinic who reported same-sex contact: their HIV seroprevalence and risk behaviors. Am J Public Health 1995;85:1366-71.
1304 21. Marrazzo JM, Koutsky LA, Handsfield HH. Characteristics of female clinic clients who report same-sex behaviour. Int J STD AIDS 2001;12:41-6. 22. Eisenberg M. Differences in sexual risk behaviors between college students with same-sex and opposite-sex experience: results from a national survey. Arch Sex Behav 2001;30:575-89. 23. Cochran SD, Mays VM, Bowen D, Gage S, Bybee D, Roberts SJ, et al. Cancer-related risk indicators and preventive screening
Marrazzo and Stine behaviors among lesbians and bisexual women. Am J Public Health 2001;91:591-7. 24. Smith E, Johnson SR, Guenther SM. Health care attitudes and experiences during gynecologic care among lesbians and bisexuals. Am J Public Health 1985;75:1086-7. 25. Cochran SD. Emerging issues in research on lesbians’ and gay men’s mental health: Does sexual orientation really matter? Am Psychol 2001;56:931-47.
www.elsevier.com/locate/ajog
Reproductive health history of lesbians: Implications for care Jeanne M. Marrazzo, MD, MPH,* Kathleen Stine, NP Department of Medicine, University of Washington, Seattle, Wash Received for publication June 18, 2003; revised December 4, 2003; accepted December 4, 2003
–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– KEY WORDS Lesbian Pregnancy Abortion Bisexuality
Objective: Parity and hormonal contraceptives modify the risk of reproductive cancers and cardiovascular disease. However, clinicians may not obtain reproductive histories from patients who self-identify as lesbian. We report lifetime pregnancy-related outcomes and hormonal contraception for 392 women who reported sexual activity with another woman in the preceding year. Study design: Among self-referred volunteers, previous pregnancy, pregnancy outcome, contraceptive use, and sexual identity were assessed with self-administered questionnaire. Results: One in 4 subjects had been pregnant, and more than 50% of the women had used oral contraceptives (mean duration, 40 months). Sixteen percent of all subjects and 63% of those who had been pregnant previously reported having 1 or more induced abortions. The most common pregnancy outcome for women younger than 25 years was induced abortion (59% of pregnancies). Identifying as ‘‘lesbian’’ or ‘‘bisexual’’ predicted neither the duration of oral contraceptive use nor a report of induced abortion. Conclusion: Previous pregnancy, induced abortion, and hormonal contraceptive use are common among women who report sex with women, regardless of self-identification as lesbian. Ó 2004 Elsevier Inc. All rights reserved.
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– Although estimates of lifetime same sex behavior vary, 1.4% to 5% of all women may be sexually active with other women.1 In the United States, an estimated 2.3 million women describe themselves (self-identify) as lesbian.2 Although numerous studies have reported that most women who self-identify as lesbians (53%-99%) have had sex with men and many of these women
Supported by a National Institutes of Health grant (R29-AI4115304). * Reprint requests: Jeanne M. Marrazzo, MD, MPH, Harborview Medical Center, Division of Infectious Diseases, 325 9th Ave, Mailbox #359931, Seattle, WA 98104. E-mail: [email protected] 0002-9378/$ - see front matter Ó 2004 Elsevier Inc. All rights reserved. doi:10.1016/j.ajog.2003.12.001
(21%-30%) continue to have sex with men,3 scant data are available on the reproductive history, including pregnancy and hormonal contraceptive use, of this group. Until recently, the major ‘‘women’s health’’ studies did not collect information on same-sex behavior or sexual identity. Because parity and hormonal contraceptive use modify the risk of important health outcomes (which include cardiovascular disease and breast, ovarian, and cervical cancers4-7) and because controversy exists about some aspects of the implementation of screening protocols, particularly for mammography, it is important that women’s health care providers routinely assess these parameters. Further, a history of pregnancy that results in abortion may indicate risk behavior that
1299
Marrazzo and Stine is associated with the acquisition of sexually transmitted diseases (STDs) that can affect a woman’s future reproductive health.8 However, lesbian patients may not receive appropriate assessment of these exposures and outcomes routinely or, particularly in the case of Papanicolaou test screening for cervical cancer, the screening interventions that are prompted by their report.9-12 In fact, routine Papanicolaou test screening is performed less frequently among lesbians than national guidelines advise,10,13,14 although sexual transmission of oncogenic genital human papillomavirus (HPV) has been reported to occur between women,10,14,15 and genital HPV may be detected in up to 40% of lesbians.14 We examined self-report of previous pregnancy, pregnancy outcome, and hormonal contraceptive use in a group of women who reported sex with another woman in the previous year and who were enrolled in a community-based study of STDs and cervical neoplasia. Of specific interest was the outcome of induced abortion, which is often an indicator of unintended pregnancy in young adult and adolescent women. For the remainder of this report, we define ‘‘lesbian’’ using the dimension of same-gender sexual behavior, as did Laumann et al.1 However, we also asked women to provide their self-defined sexual identity, which included the term lesbian as an option; we specify the use of this term as such when discussing these results.
Material and methods Women were recruited from February 1998 through December 2001 through advertisements that were posted in community venues (restaurants, bookstores, clubs, and bars), newspaper and magazine articles, and referral from community clinics. Because self-identifying as lesbian may not predict actual participation in same-sex behavior or its frequency, we oriented recruitment materials to women who had sex with other women, regardless of self-identification. However, we also asked women to define themselves as ‘‘lesbian,’’ ‘‘bisexual,’’ or ‘‘straight.’’ Women were eligible for enrollment if they were between the ages of 16 and 45 years, could provide written informed consent, and reported having sex with another woman in the preceding year. The timeframe of 1 year for sexual exposure to female partners was chosen because we also assessed risk of genital HPV acquisition from female partners, as previously described.10,14 Sexual behavior with either male or female partners was defined as contact between oral and/or genital mucosa to genital mucosa. When participants phoned to make an appointment, they received by mail an extensive standardized questionnaire that detailed demographic characteristics and medical, reproductive, and sexual history, which they
completed and brought to their appointment. The questionnaire specifically included information on insurance status, cigarette and alcohol use, the number of previous pregnancies, age at pregnancy, pregnancy outcome, douching history, types of hormonal contraceptive and dates of use, Papanicolaou test history, self-reported history of STD, current genital symptoms, number of lifetime male and female sex partners, and sexual behaviors. Women were asked to define themselves as ‘‘lesbian,’’ ‘‘bisexual,’’ or ‘‘straight.’’ The questionnaire was reviewed for completion with the subject by the research clinician (K.S.) or principal investigator (J.M.M.). Concomitant clinical assessment included a pelvic examination with testing for genital HPV by polymerase chain reaction, assessment of vaginal bacteria, and Papanicolaou cervical cytologic condition, as reported previously.10,16 Statistical analysis was performed using SPSS software (SPSS Inc, Chicago, Ill). Direct comparisons of proportions were made using Pearson’s chi-squared test. Continuous variables were compared with the use of the Student t test or the Mann-Whitney test for nonparametric data. Multivariate analysis was performed by logistic regression techniques. For all variables in the multivariate analysis, data that were missing were categorized as ‘‘missing’’ and included in the analysis. Because subjects were not asked specifically whether each pregnancy was intended, the primary outcome for the multivariate analysis was the report of induced abortion, a reasonable surrogate for unintended pregnancy. Tests of significance were 2-tailed and used a significance level of a probability value of !.05. The study’s procedures were approved at the onset and reviewed annually by the University of Washington Human Subjects Research Review Committee.
Results A total of 392 women were recruited, most of whom responded to posted advertisements in community venues or who were referred by a friend or partner (Table I). The women were predominantly white, relatively highly educated, and !30 years old (median age, 28 years). Although mean income was relatively high, 31% of the women reported having no current health insurance coverage. Most women (89%) reported no current genitourinary symptoms; the remainder of the women reported abnormal or increased vaginal discharge or itching. Although most women (66%) self-identified as lesbian, 80% of the women also reported having had intercourse with a male partner during their lifetime, and 28% of the women reported doing so in the previous year. Of the 257 women who self-identified as lesbian, 187 women (73%) had ever had sex with a man, and 22 women (8.6%) had done so in the previous year.
1300 Table I
Marrazzo and Stine Characteristics of study subjects (n = 392 women)
Characteristic Age (median, 28 y; range, 17-56 y) !25 y 25-30 y 31-39 y O39 y Race White Black Asian/Pacific Island Native American Other Hispanic* Current health insurance Monthly individual income (mean, $1870; range, 0-$7200) !$1800 O$1800 Not reported Marital status Never married to a man Divorced Ever married, not divorced Educational level High school diploma Some college College degree or higher Previous pregnancy Hormonal contraceptive use Current Ever (includes current) Before 1975 Never Male partners Sex with male, ever Sex with male, previous year Lifetime male partners (median) Lifetime female partners (median) Recruitment sourcey Posted advertisements/article Clinic referral Friend or partner
Subjects (n) 119 113 100 60
(30%) (29%) (26%) (16%)
344 7 13 8 20 21 270
(88%) (1.8%) (3.4%) (2.0%) (5.2%) (5.4%) (69%)
194 (49%) 154 (39%) 44 (12%) 337 (86%) 43 (11%) 12 (3.1%) 16 137 239 97
(4.2%) (35%) (61%) (25%)
24 206 23 176
(6.1%) (53%) (5.9%) (45%)
313 (80%) 110 (28%) 7 6 86 (41%) 21 (10%) 100 (48%)
* Eight of the 21 women who reported Hispanic ethnicity reported no race category in addition to ethnicity. y Two hundred nine women were specifically queried after the questionnaire was modified to include this information; percentages refer to this denominator.
The number of lifetime male partners did not differ between women who identified as lesbian and women who identified as bisexual (P=.12). Among all subjects, 97 women (25%) had been pregnant at least once, and more than one half of the women had used oral contraceptives at some point during their lifetime. Sixty-one women reported having had R1 abortions (16% of all subjects; 20% of those who had ever had sex with a man; and 63% of those who had ever been
pregnant). Pregnancy outcomes and hormonal contraceptive use history are stratified by demographic characteristics, sexual history, and self-defined sexual identity in Table II. Not surprisingly, the report of these outcomes increased with the increasing age of subjects, with more than one half of all women R40 years old reporting a previous pregnancy or ever having used oral contraceptives. There were no differences in reported frequency of these outcomes when women were stratified by educational level or current income. Women who self-identified as bisexual were more likely to report a previous pregnancy or ever having used oral contraceptives; however, neither the prevalence of the report of previous abortion nor the duration of oral contraceptive use significantly differed between women who identified as lesbian compared with those who identified as bisexual. Finally, all 3 outcomes (pregnancy, abortion, and oral contraceptive use) were associated strongly with a reported increasing number of lifetime male sex partners. Of the 206 women who reported having used oral contraceptives, information on type and duration was available for 182 women (88%). Mean duration of use was 40 months (range, 1- 192 months). Twenty-five women (6% of all subjects, and 20% of subjects over 35 years old) used oral contraceptives before 1975. Two women reported the use of a low-dose estrogen compound and a progesterone-only compound, respectively; most of the remaining women did not recall the specific type. However, most preparations that were available before 1975 contained relatively high concentrations of ethynyl estradiol (R50 mg/mL). One of these 23 women reported a history of breast cancer, and 10 women (43%) reported that a family member had had breast cancer (first-degree relative in 4 women [17%] and second-degree in 7 women [30%]). Seventeen of these 23 women (74%) reported their self-identity as lesbian. Table III shows the risk factors for the report of a history of induced abortion among subjects who reported ever having had sex with a man (n = 313 women). Significant associations were seen in univariate analysis for age at first pregnancy of 20 to 24 years, age at first sex with male partner of %17 years, and increasing number of lifetime male partners. In the multivariate model, however, only increasing number of lifetime male partners remained associated significantly with this outcome (adjusted odds ratio for women who reported R8 male partners relative to those reporting %4 male partners, 6.9; P = .05). Although younger age at first sex with a female partner and current lower median income were associated with an increased likelihood of report of induced abortion, these associations were not statistically significant (P = 0.4 for both). As shown in Figure, the 97 women who reported ever having been pregnant experienced 176 obstetric outcomes, including live birth in 20 women (21%), induced abortion in 28 women (29%), and fetal loss in
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Marrazzo and Stine 17 women (18%). One woman reported a molar pregnancy, and 1 woman reported an ectopic pregnancy. Most pregnancies occurred when the women were in their third decade (20-29 years old), but 1 in 4 pregnancies (26%) occurred during adolescence. The most common pregnancy outcome for women younger than 25 years of age was induced abortion, which occurred in 59% of all pregnancies in this age group. Among women who reported a history of induced abortion, the median number of these events was 1 (range, 1-4 events).
Comment Among women reporting sex with another woman in the previous year, most of whom self-identified as lesbian, lifetime reports of previous pregnancy, oral contraceptive use, and induced abortion were common. Overall, 25% of women had been pregnant at least once, and 16% had had an abortion. Most women (63%) who had ever been pregnant had had at least 1 abortion. One fifth of the subjects who specifically self-identified as lesbian had been pregnant at least once; 12% of them had had an induced abortion, and almost one half of them had ever used oral contraceptives. Of related importance, the number of reported lifetime male sex partners did not differ by whether women identified as lesbian or bisexual. Because these findings demonstrate that self-identification as lesbian does not preclude the previous use of oral contraceptives or pregnancy-related outcomes consistently, providers must address these issues with all adult women patients, regardless of stated sexual identity or behavior. These findings may be particularly important for clinics with a traditional family planning focus, because these may serve as the primary entry point of care for many lesbians, particularly those with limited resources. Further, our results suggest that inclusion of some measure of same-sex behavior is warranted even in surveys that have traditionally focused on reproductive health outcomes of women who were assumed to have heterosexual experience exclusively. Our findings generally agree with those of the few published studies that have reported on reproductive outcomes among lesbians. Only 1 recent large-scale study that included pregnancy and hormonal contraceptive use history reported results that were stratified for respondents’ same-sex behavior.11 Among participants in the Women’s Health Initiative, ever use of oral contraceptives was similar between lesbians and heterosexual women, and 35% of the women reported ever having been pregnant.11 Among 2356 women who were surveyed in 1980, 48% of 1921 self-identified lesbians reported ever using oral contraceptives, and 13% of them reported ever using an intrauterine device; 23% of these
Table II Pregnancy outcomes and hormonal contraceptive use by demographic characteristics and self-reported sexual identity*,y
Characteristic Current age !25 25-39 R40 P (trend)* Education %High school + some college RCollege degree P* Race White Nonwhite P* Current monthly household income !$1800 O$1800 P* Self-defined sexual identity Lesbian Bisexual P* Lifetime male sex partners %3 4-7 8-15 R16 P (trend)*
Hormonal Previous Abortion contraceptive pregnancy (n) history (n ) use ever (n) 10 (8.4%) 53 (25%) 34 (57%) !.001
8 (6.7%) 37 (18%) 16 (27%) NS
52 (44%) 112 (53%) 38 (63%) !.02
49 (32%)
28 (18%)
76 (50%)
48 (21%) .16
33 (14%) .29
126 (54%) .52
81 (24%) 16 (34%) .15
53 (15%) 8 (17%) .27
181 (53%) 21 (45%) .34
43 (22%) 45 (30%) .13
27 (14%) 30 (20%) .66
90 (47%) 83 (55%) .15
52 (21%) 44 (34%) .006
31 (12%) 30 (23%) .5
113 (45%) 87 (68%) !.001
7 (7.6%) 18 (24%) 25 (35%) 45 (59%) !.001
2 (2.2%) 9 (12%) 19 (27%) 30 (39%) .06
36 (39%) 52 (70%) 47 (66%) 60 (79%) !.001
* Percentages refer to the proportion of women who experienced the outcome relative to all women in a given category (for example, 7.8% of women who were !25 years old and who reported a previous pregnancy). y The level of significance of differences within demographic categories for each of the outcome variables (for example, increasing age that is associated significantly with the outcome of previous pregnancy [P !.001 for trend], but the current household income was not [P = .13]).
women had ever been pregnant, with 53% reporting elective abortion and 20% reporting spontaneous abortion.17 As recently reported for another communitybased sample of lesbians,18 our subjects reported a lower prevalence of parity than that of women in the United States in general. However, relative to data for women in the United States reported in the National Survey of Family Growth, our subjects had a comparable estimated rate of induced abortions.19
1302 Table III
Marrazzo and Stine Risk factors for report of previous abortion among subjects with a history of sex with men (n = 313 women)*
Characteristic Age at first pregnancy %19 y 20-24 y R25 y Race Nonwhite White Education %High school + some college RCollege degree Self-defined history of problem drinking Income (monthly) !$1800 O$1800 Age at first sex with male partner %17 y R17 y Age at first sex with female partner %20 y R20 y Lifetime male sex partners (n) %3 4-7 R8
Subjects (n)
Univariate odds ratio (95% CI)
P value
Multivariate odds ratio (95% CI)
P value
39 31 25
1.9 (0.7, 5.4) 3.7 (1.2, 12) Referent
.5 .03
3.1 (0.8, 10) 2.9 (0.8, 12) Referent
.11 .11
34 272
1.2 (0.6, 3.0) Referent
.5
0.3 (0.1, 1.2)
.2
127 186 67
1.2 (0.8, 1.9) Referent 1.0 (0.6, 1.7)
.3
.4
.9
0.6 (0.2, 1.8) Referent 0.5 (0.1, 1.6)
121 157
1.6 (0.9, 2.8) Referent
.7
1.6 (0.5, 4.6)
.4
167 139
1.7 (1.0, 1.4) Referent
.04
0.7 (0.2, 2.2)
.5
165 147
0.6 (0.3, 1.1) Referent
.08
1.2 (0.4, 3.8) Referent
.4
92 74 147
Referent 6.2 (1.3, 30) 23 (5.6, 98)
.02 !.001
Referent 1.6 (0.2, 12) 6.9 (1.0, 46)
.4
.7 .05
* Numbers in columns may not add to 313, because information on some characteristics was not available for all subjects.
Figure Pregnancy outcomes among 97 women by age at event (total events = 176 [does not include 1 episode each of ectopic pregnancy and molar pregnancy]). The open portion of the bars represents induced abortion; the gray portion of the bars represents fetal loss; and the closed portion of the bars represents live birth.
Beyond the assessment of reproductive health history, our findings emphasize that self-identification as lesbian should not preclude the performance of a complete sexual health history. Lesbians who are also currently sexually active with men may demonstrate increased sexual risk-taking behavior in some settings, which is a finding that is supported by the high proportion of pregnancies that ended in abortion. Among
women who attended STD clinics, the report of sex with women in addition to sex with men has been associated with a high prevalence of human immunodeficiency viruserelated risk behaviors, including sex with gay or bisexual men, the use of injection drugs, the use of crack cocaine, and the exchange of sex for drugs or money.20,21 In the 1997 College Alcohol Study, comprised of 14,251 randomly selected US college students, women who reported sex with both men and women were more likely to report multiple sex partners than peers with only opposite-sex partners.22 Despite these findings, several factors may contribute to lesbians not receiving thorough evaluation for reproductive health.11,23 First, some evidence suggests that providers may assume that because a woman self-identifies as lesbian, sexual and reproductive histories are of relatively little import. 10 Most studies of preventive screening that is related to these assessments have focused on lesbians’ experience with Papanicolaou tests, which may be a reasonable surrogate for reproductive health assessment and screening. As previously reported, our subjects reported being told they did not need Papanicolaou tests because they were lesbians; the provider was a physician in 90% of these events.10 Second, lack of medical insurance may contribute; despite the report of relatively high income among our subjects,
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Marrazzo and Stine almost one third of them did not have health insurance. Third, some studies have noted that most lesbians (53%72%) do not disclose their sexual behavior to physicians when they seek medical care.24 In a survey of 6935 selfidentified lesbians, disclosure of sexual orientation was associated favorably with the receipt of appropriate Papanicolaou test screening.9 Finally, lesbians who do not have sex with men are not likely to access venues that provide reproductive health care for the sole purpose of obtaining birth control, which effectively eliminates another ‘‘routine’’ opportunity for assessment and screening. Our study has important limitations. First, subjects were self-referred, and may not be representative of all lesbians. Specifically, women who self-refer to studies that recruit on the basis of clearly-stated ‘‘sexual minority’’ behavior conceivably could be biased towards the inclusion of women who are more comfortable discussing their current and past sexual and pregnancy history. This could bias estimates for outcomes (such as induced abortion upwards) that are relative to those estimates that are derived from a population-based survey. However, population-based sampling methods do not generate reliably substantial, and possibly diverse, representation of populations that may be less visible because of minority status (such as sexual orientation).25 Second, most of our subjects were white. Because disparities in health care seeking and risk behavior among lesbians may be modified by race,12 a more comprehensive study of racially diverse groups of lesbians is needed. Third, our sample size may have been too small to detect statistical significance for several associations. Finally, we did not ask subjects specifically whether each pregnancy was intended, nor did we assess specific reasons for the use hormonal contraceptives; subjects may have used them for indications unrelated to contraception. Erroneous assumptions about the reproductive history of lesbians may place them at increased risk for delayed detection of adverse outcomes. Specifically, a provider’s knowledge of a lesbian’s reproductive history can help to inform counseling about preventive behaviors, individual decisions about screening, and risk for outcomes for diseases other than STDs, including breast and cervical cancers. Our findings support the need for an investigation in a larger number of women. Such information will help to clarify messages that are provided to lesbians about their risk of outcomes that are related to these factors and should direct efforts to educate providers about the appropriate care and counseling of lesbians.
Acknowledgments We thank Laura Koutsky for general support of this study and Alison Starling for assistance with data management.
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1304 21. Marrazzo JM, Koutsky LA, Handsfield HH. Characteristics of female clinic clients who report same-sex behaviour. Int J STD AIDS 2001;12:41-6. 22. Eisenberg M. Differences in sexual risk behaviors between college students with same-sex and opposite-sex experience: results from a national survey. Arch Sex Behav 2001;30:575-89. 23. Cochran SD, Mays VM, Bowen D, Gage S, Bybee D, Roberts SJ, et al. Cancer-related risk indicators and preventive screening
Marrazzo and Stine behaviors among lesbians and bisexual women. Am J Public Health 2001;91:591-7. 24. Smith E, Johnson SR, Guenther SM. Health care attitudes and experiences during gynecologic care among lesbians and bisexuals. Am J Public Health 1985;75:1086-7. 25. Cochran SD. Emerging issues in research on lesbians’ and gay men’s mental health: Does sexual orientation really matter? Am Psychol 2001;56:931-47.