Advertisement

Receipt of preventive health care services by lesbians1

      Abstract

      Background: We measured receipt of age-appropriate preventive health services by lesbians and assessed whether provider and individual characteristics, including disclosure of sexual orientation, are independently associated with receipt of these services.
      Methods: A questionnaire was printed in a national biweekly gay, lesbian, and bisexual news magazine, and self-identified lesbians living in all U.S. states (N =6935) responded to the survey. Main outcome variables were receipt of a Pap smear within the preceding 1 and 2 years and, for women aged ≥50, receipt of a mammogram within the past 1 and 2 years.
      Results: Fifty-four percent had Pap smears within 1 year and 71% within 2 years, with increasing rates among older and more educated respondents. Seventy percent of respondents aged ≥50 had a mammogram in the past year, and 83% within 2 years; rates did not vary significantly controlling for education. Sixty percent had disclosed their sexual orientation to their regular health care provider. Controlling for patient and provider characteristics, disclosure was independently associated with receipt of Pap smears, but not mammograms.
      Conclusions: It is important for providers to identify their lesbian patients’ unmet needs for preventive health care. Additionally, it is important for providers to provide complete and appropriate preventive health care for their lesbian patients. Further research is needed to determine why lesbians are not receiving Pap smears at the recommended rate and whether this disparity is reflective of aspects of cervical cancer screening or indicates a more general problem with access to health care including receipt of preventive services.

      Keywords

      A lthough a variety of factors have been shown to affect access to health care and health seeking behaviors,
      • Andersen R.M
      Revisiting the behavioral model and access to medical care does it matter?.
      ,
      • Hulka B.S
      • Wheat J.R
      Patterns of utilization the patient perspective.
      the impact of sexual orientation on receipt of preventive health services remains largely unknown. A recent report from the Institute of Medicine urges researchers to focus on the understudied issues of lesbian health, including the receipt of preventive health services.
      • Solarz A.L
      Data from previous studies suggest that lesbians are at increased risk for not receiving important preventive health services such as Pap smears and mammograms.
      • Johnson S.R
      • Guenther S.M
      • Laube D
      • et al.
      Factors influencing lesbian gynecologic care a preliminary study.
      ,
      • Johnson S.R
      • Smith E.M
      • Guenther S.M
      Comparison of gynecologic health care problems between lesbians and bisexual women a survey of 2345 women.
      ,
      • Bradford J
      • Ryan C
      ,
      • Zeidenstein L
      Gynecological and childbearing needs of lesbians.
      ,
      • Rankow E.J
      • Tessaro I
      Cervical cancer risk and Papanicolaou screening in a sample of lesbian and bisexual women.
      ,
      • Roberts S.J
      • Sorensen L
      Health related behaviors and cancer screening of lesbians results from the Boston Lesbian Health Project.
      ,
      • Price J.H
      • Easton A.N
      • Tellijohann S.K
      • Wallace P.B
      Perceptions of cervical cancer and Pap smear screening behavior by women’s sexual orientation.
      ,
      • Carroll N.M
      Optimal gynecologic and obstetric care for lesbians.
      Some information is available from cohort studies that compare lesbians’ receipt of preventive services with that of heterosexual women in the same sample of women.
      • Price J.H
      • Easton A.N
      • Tellijohann S.K
      • Wallace P.B
      Perceptions of cervical cancer and Pap smear screening behavior by women’s sexual orientation.
      ,

      Koh A. Use of preventive health behaviors by lesbian, bisexual, and heterosexual women: questionnaire survey. West J Med 2000. In press.

      Large population-based studies to assess the effect of sexual orientation and disclosure of sexual orientation on receipt of preventive health services have not yet been performed. However, findings from a recent population-based study that included a small sample of lesbians indicated a negative association between lesbian sexual orientation and receipt of preventive services.

      Diamant AL, Spritzer K, Wold C, Gelberg L. The effect of sexual orientation on health behaviors, health status, and access to and use of health care: a population-based study of women. Under review.

      Individual patient characteristics such as age, income, education, and health insurance are associated with receipt of preventive services.
      • Aday L.A
      • Andersen R
      A framework for the study of access to medical care.
      ,
      • Weissman J.S
      • Stern R
      • Fielding S.L
      • et al.
      Delayed access to health care risk factors, reasons, and consequences.
      ,
      • Aday L.A
      • Awe W.C
      Health sources utilization models.
      ,
      • Millman M
      Institute of Medicine Committee on Monitoring Access to Personal Health Care Services
      However, it is important to identify other predictors that will allow for the receipt of maximal gender- and age-specific health care. In addition, patients who have a regular health care provider or site of care are more likely to receive preventive health care services.
      • Lambrew J.M
      • DeFirese G.H
      • Carey T.S
      • et al.
      The effects of having a regular doctor on access to primary care.
      ,
      • Weissman J.S
      • Stern R
      • Fielding S.L
      • et al.
      Delayed access to health care risk factors, reasons, and consequences.
      Failure to receive necessary medical care may be due to a number of factors that inhibit some women from seeking needed medical care or from disclosing their sexual orientation to a health care provider.
      • Johnson S.R
      • Guenther S.M
      • Laube D
      • et al.
      Factors influencing lesbian gynecologic care a preliminary study.
      ,
      • Johnson S.R
      • Smith E.M
      • Guenther S.M
      Comparison of gynecologic health care problems between lesbians and bisexual women a survey of 2345 women.
      ,
      • Bradford J
      • Ryan C
      ,
      • Zeidenstein L
      Gynecological and childbearing needs of lesbians.
      ,
      • Dardick L
      • Grady K.E
      Openness between gay persons and health professionals.
      ,
      • Smith E.M
      • Johnson S.R
      • Guenther S.M
      Health care attitudes and experiences during gynecologic care among lesbians and bisexuals.
      ,
      • Cochran S.D
      • Mays V.M
      Disclosure of sexual preference to physicians by black lesbian and bisexual women.
      ,
      • Bybee D
      ,
      • Warshafsky L
      ,

      O’Hanlan K. Lesbian health and homophobia: perspectives for the treating obstetrician/gynecologist. Curr Probl Obstet Gynecol Fertil 1995; July/August:97–133.

      Previous research has documented that lesbians may be hesitant to disclose their sexual orientation to a health care provider,
      • Cochran S.D
      • Mays V.M
      Disclosure of sexual preference to physicians by black lesbian and bisexual women.
      yet, we found no evidence that disclosure of one’s sexual orientation has an effect on receiving preventive health services.
      This article presents findings on receipt of preventive health services among lesbians in the largest national sample to date.
      • Diamant A.L
      • Schuster M
      • McGuigan K
      • Lever J
      Lesbians’ sexual histories with men implications for taking a sexual history.
      The main objectives of our analyses were threefold: (1) to measure self-identified lesbians’ receipt of age-appropriate preventive health services (specifically Pap smears and mammograms), (2) to assess whether a disparity in receipt of Pap smears and mammograms exists between lesbians and comparable women in the general U.S. population, and (3) to evaluate whether disclosure of a woman’s sexual orientation as a lesbian and various other patient and provider characteristics are independently associated with the receipt of preventive health services.
      Based on findings from previous studies, we hypothesized lesbians’ receipt of Pap smears and mammograms would be lower than age- and education-adjusted rates for women in the general population. We also hypothesized a positive association between disclosure of sexual orientation to one’s regular health care provider and receipt of these preventive screening tests. Data from older studies suggest a negative relationship insofar as disclosure was linked to negative experiences in the medical system; however, social acceptance of lesbians has increased considerably in the last decade.
      • Nardi P.M
      The globalization of the gay and lesbian socio-political movement some observations about Europe with a focus on Italy.
      ,

      It’s normal to be queer. Economist 1996;338:68–70.

      The positive direction of our hypothesis is based on our assumptions that personal decisions to disclose one’s sexual orientation are correlated with patient and physician characteristics that may also have a positive effect on receipt of preventive health care. Patient characteristics may include greater level of comfort in disclosing sexual orientation and in reporting entire sexual histories, as well as greater awareness of the importance of health promotion. In addition, a correlation may exist among physicians; those practitioners who include sexual orientation in the medical history may be more likely to provide preventive health care services.

      Methods

      Survey instrument

      Three researchers (including MS and JL) developed a 186-item questionnaire and had it printed in The Advocate, a biweekly national news magazine for gay men, lesbians, and bisexual men and women. The questionnaire appeared as a several-page insert in the center of the March 21, 1995, issue and included a postage-paid return-addressed mailer. The questionnaire included items pertaining to sociodemographic characteristics, self-identified sexual orientation, provider/site for health care, disclosure of one’s sexual identity to a health care provider, gynecologic/obstetric history including a history of sexually transmitted diseases (STDs) and irregular Pap smears, use of oral contraceptives, history and method of conception, history of sexual activity, use of alcohol and tobacco, and receipt of preventive health services, as well as other topics and items not included in these analyses. We submitted the study protocol to the university’s Human Subjects Protection Committee, and the protocol received Institutional Review Board approval.

      Subjects

      Subscription and marketing information at the time of the survey indicated that approximately 88,000 copies of each issue of The Advocate were distributed, with a female readership of approximately 24,000. We received 7929 responses; we have no information to compare respondents with nonresponders. The analysis sample for this article consists of 6935 U.S. women from all 50 states who self-identified as lesbian based on their response to the first item of the survey, “How do you describe your sexuality?” Women who listed their orientation as bisexual or unsure (n =862) were excluded from this analysis as were 132 women from 18 foreign countries. We included only lesbians because we were interested in assessing receipt of preventive services among a population of women who had been shown previously to receive age-specific preventive health services at lower rates than women in the general U.S. population, with the disparity attributed to their sexual orientation.

      Outcome variables

      The main outcome variables of this study are receipt of age-specific preventive health services (i.e., Pap smear and mammogram) within 1 and 2 years. It is important to note that the recommendations for cervical cancer screening (i.e., Pap smears) have changed over time. Around the time of the survey, the recommendations for Pap smears had recently changed from annual testing to screening every 3 years for women at low risk for cervical cancer
      U.S. Preventive Services Task Force
      ; however, it is unclear how well these recommendations had disseminated into the medical community and general population. At the time data were collected for this study, national rates for cervical cancer screening were still being reported as annual rates.

      Centers for Disease Control and Prevention, National Center for Health Statistics. National health interview survey. NHIS health promotion/disease prevention year 2000 objectives supplement. Hyattsville, MD: Public Health Service, 1994.

      The accepted standard of care for breast cancer screening at the time of the study included annual mammography for women aged ≥50. The recommendation for screening among women aged 40 to 49 without a significant family history of breast cancer varies among health care organizations
      U.S. Preventive Services Task Force
      ,
      American Cancer Society
      ,

      National Cancer Institute. Statement from the National Cancer Institute on the National Cancer Advisory Board recommendations on mammography. CancerNet press release March 27, 1997.

      ,
      American Medical Association
      and remains controversial.

      Independent variables

      Our hypothesized independent variables for receipt of Pap smears and mammograms include the following: whether or not a woman had a regular provider/site for health care (i.e. private doctor’s office, health maintenance organization, or freestanding or hospital-based outpatient clinic), and whether the respondent had disclosed her sexual orientation to her health care provider. Because of the association among cervical cancer, human papilloma virus (HPV), and sexual activity, we examined data about sexual history with men, including lifetime history of vaginal intercourse, lifetime history of vaginal intercourse without a condom, and lifetime number of male sexual partners. Variables pertaining to respondents’ past gynecologic/obstetric histories were dichotomous and included diagnosis of irregular Pap smears; any history of STD (gonorrhea, chlamydia, trichomoniasis, pelvic inflammatory disease, syphilis, genital or anal herpes, genital or anal warts—i.e., HPV—and HIV); and any history of breast cancer or benign breast mass.
      We also included variables for oral contraceptive use (≥ 6 months) and parity as part of the obstetric and gynecologic history because of the possible increased risk for breast cancer
      • Ursin G
      • Ross R.K
      • Sullivan-Halley J
      • Hanisch R
      • Henderson B
      • Bernstein L
      Use of oral contraceptives and risk of breast cancer in young women.
      ,

      Van Os WA, Edelman DA, Rhemrev PE, Grant S. Oral contraceptives and breast cancer risk. Advances in contraception 1997;13:63–9.

      ,
      • Brinton L.A
      • Daling J.R
      • Liff J.M
      • et al.
      Oral contraceptives and breast cancer risk among younger women.
      as well as the protective effects against ovarian and endometrial cancer from oral contraceptives.
      • dos Santos Silva I
      • Swerdlow A.J
      Recent trends in incidence of and mortality from breast, ovarian and endometrial cancers in England and Wales and their relation to changing fertility and oral contraceptive use.
      ,
      • Grimes D.A
      • Economy K.E
      Primary prevention of gynecologic cancers.
      ,
      • Oriel K.A
      • Hartenbach E.M
      • Remington P.L
      Trends in United States ovarian cancer mortality, 1979–1995.
      Because of the known association between tobacco use and cervical cancer,
      • Bornstein J
      • Rahat M.A
      • Abramovici H
      Etiology of cervical cancer current concepts.
      ,
      • Hirose K
      • Hamajima N
      • Takezaki T
      • et al.
      Smoking and dietary risk factors for cervical cancer at different age group in Japan.
      and alcohol use and breast cancer,
      • Smith-Warner S.A
      • Spiegelman D
      • Yaun S.S
      • et al.
      Alcohol and breast cancer in women a pooled analysis of cohort studies.
      ,
      • Bradley K.A
      • Badrinath S
      • Bush K
      • Boyd-Wickizer J
      • Anawalt B
      Medical risks for women who drink alcohol.
      ,
      • Tseng M
      • Weinberg C.R
      • Umbach D.M
      • Longnecker M.P
      Calculation of population attributable risk for alcohol and breast cancer (United States).
      we included respondents’ current regular use of tobacco and alcohol in our analyses. Current regular use was defined as a few times a month or more frequently. Our covariates included age, race/ethnicity, education, income, and size of residential community.

      Statistical analyses

      We performed bivariate analyses using the chi-square test at a level of significance of p<0.05 to assess the association between categorical variables and receipt of the screening tests. We used multivariate binomial regression with the log link function to calculate adjusted prevalence ratios and 95% confidence intervals to test for independent associations between our predictor variables and the dependent variable in each model while controlling for covariates. In the first model, the dependent variable was receipt of a Pap smear within 2 years for all lesbians; in the second model, the dependent variable was receipt of a mammogram within 2 years for lesbians aged ≥50.
      We also assessed variation in rates for receipt of Pap smears and mammograms within 1 year between lesbians in this sample and women in the general U.S. population. We performed this comparison using data from a nationally representative sample of women collected by the Gallup Poll in 1997 for a study of preventive screening behaviors sponsored by the American College of Pathologists.

      Gallup Poll, 1997. Data provided courtesy of the college of American Pathologists and the Gallup Organization, March 5, 1998.

      We used data from the Gallup Poll because it could be stratified by education and age, and similar data were not available to us from large population-based studies. Comparison of findings from the two samples was performed using the chi-square test at a level of significance of p<0.05. All statistical analyses were performed using SAS 6.12.

      SAS Institute, Inc. SAS 6.12. Cary, NC: SAS Institute Inc., 1990.

      Results

      Sample characteristics

      The median age for respondents was 34 years. Although ages range from 15 to 93, 85% were aged 25 to 49 (Table 1). The majority of respondents were Caucasian, almost two thirds were college graduates, the median income range was $20,000 to $30,000, and respondents were from urban and rural communities.
      Table 1Demographic and other characteristics of a sample of lesbians (N = 6935)
      Characteristic%No.
      Number of respondents.
      Age
      <25 years9654
      25–49 years855878
      ≥50 years6403
      Race/ethnicity
      Caucasian886036
      Hispanic/Latina7459
      African American2166
      Asian/Pacific Islander/Filipino166
      American Indian/Alaskan Native158
      Other2113
      Education
      Some college or less372569
      College graduate221539
      Graduate professional/school412810
      Income
      <$20,000302047
      $20,001–$50,000553758
      >$50,000161085
      Size of community:
      >1 million352432
      100,000–1 million302077
      <100,000241659
      Regular provider815622
      Disclosed sexual orientation to a regular health care provider603373
      Female703935
      Lifetime history of vaginal intercourse724994
      Lifetime histories of vaginal intercourse without condom use among lesbians894431
      Gynecologic/medical history
      Items in gynecologic/medical history are not mutually exclusive and, therefore, do not total 100%.
      Lumps or fibroids on breast biopsy12834
      Abnormal Pap smear171202
      Any sexually transmitted disease
      Includes gonorrhea, chlamydia, trichomoniasis, pelvic inflammatory disease, syphilis, herpes, warts, or HIV.
      171195
      Use of oral contraceptives
      For 6 months or more.
      372550
      Conceived a child12853
      Substance use
      Alcohol—current
      Lesbians’ response to the question “How often do you use the following substance?” was two or more times daily.
      634370
      Tobacco—current
      Lesbians’ response to the question “How often do you use the following substance?” was two or more times daily.
      271897
      a Number of respondents.
      b Items in gynecologic/medical history are not mutually exclusive and, therefore, do not total 100%.
      c Includes gonorrhea, chlamydia, trichomoniasis, pelvic inflammatory disease, syphilis, herpes, warts, or HIV.
      d For 6 months or more.
      e Lesbians’ response to the question “How often do you use the following substance?” was two or more times daily.
      Most women (81%) had regular health care providers or sites of care, and 60% of these women had disclosed their sexual orientation to their regular providers (Table 1). Seventy percent of regular providers were female, and 71% of respondents with regular female providers had disclosed their sexual orientation to their physicians compared with 47% of respondents with regular male providers (p<0.001).
      Seventy-two percent of respondents reported lifetime histories of vaginal intercourse, and 89% of these women reported ever engaging in vaginal intercourse without condom use. Twelve percent of respondents had fibroids or breast lumps on breast biopsy, and 17% had ever had abnormal Pap smears. Seventeen percent of respondents reported lifetime histories of having had STDs, including 5% with histories of genital or anal warts (HPV). Thirty-seven percent of respondents had used oral contraceptives for ≥6 months, and the rates increased with age (25% for women <25 years old, 38% for women aged 25 to 49, 45% for women ≥50, p<0.001). Overall, 12% of women had biological children, with the highest rates among women aged ≥50 (3% vs 11% vs 42%, p<0.001). Sixty-three percent of respondents reported some use of alcohol, and 27% reported current use of tobacco.

      Receipt of pap smears

      Fifty-four percent of women reported receipt of Pap smears within the preceding year, and an additional 17% (for a total of 71%) of respondents had received Pap smears within 2 years (Table 2). In bivariate analysis, older age, higher educational attainment, and greater annual income were associated with higher rates of cervical cancer screening (Table 3). Seventy-five percent of women with regular providers had received Pap smears in the past 2 years, compared with 52% of women without regular health care providers. Women who disclosed their sexual orientation were considerably more likely than those who did not disclose to have had Pap smears within the past 2 years, both among those with regular providers (82% vs 64%, p<0.001) and among those without regular providers (71% vs 36%, p<0.001). Respondents who had histories of vaginal intercourse without condom use and those with histories of STDs were each more likely to have received Pap smears within the preceding 2 years, whereas women who reported tobacco use were less likely than nonsmokers to have had Pap smears within 2 years. Of note, 8% of women had never had Pap smears, including 4% of women who had histories of vaginal intercourse without condom use.
      Table 2Receipt of preventive screening tests
      Within 1 year % (n)Within 2 years % (n)
      Pap smear (n = 6919)54 (3715)71 (4896)
      Mammogram (n = 401)70 (280)83 (334)
      Table 3Receipt of a Pap smear for cervical cancer screening (N = 6935) or a mammogram for breast cancer screening (N = 403)
      Receipt of a mammogram was assessed for women aged ≥50 years only.
      within 2 years
      ––– Reference categories (i.e., omitted variables);
      ,
      CI, confidence interval
      Independent VariablesPap smear within 2 yearsMammogram within 2 years
      Unadjusted %Adjusted prevalence ratio (95% CI)Unadjusted %Adjusted prevalence ratio (95% CI)
      Age
      <25 years550.03 (−0.04, 0.05)
      25–49 years72–––
      Item not included in the model to assess receipt of a mammogram within 2 years.
      Item not included in the model to assess receipt of a mammogram within 2 years.
      ≥50 years83
      p <0.001.
      0.04 (0.01, 0.06)
      p <0.05,
      Race/ethnicity
      Caucasian710.01 (−0.02, 0.04)850.07 (−0.11, 0.25)
      Non-caucasian69–––71
      p <0.05,
      –––
      Education
      Some college or less62−0.06 (−0.08, −0.03)
      p <0.001.
      78−0.04 (−0.14, 0.07)
      Finished college71−0.01 (−0.04, 0.01)73−0.11 (−0.25, 0.04)
      Graduate school78
      p <0.001.
      –––87
      p <0.05,
      –––
      Individual income
      <$20,00059−0.06 (−0.09, −0.03)
      p <0.001.
      73−0.05 (−0.20, 0.10)
      $20,000–$50,00074−0.02 (−0.04, 0.01)83−0.02 (−0.13, 0.09)
      >$50,00082
      p <0.001.
      –––89
      p <0.05,
      –––
      Size of community
      Rural68−0.01 (−0.05, 0.02)77−0.04 (−0.17, 0.09)
      City—small65−0.02 (−0.05, 0.01)820.01 (0.10, 0.13)
      City—medium720.01 (−0.02, 0.03)880.03 (−0.09, 0.14)
      City—large75
      p <0.001.
      –––84–––
      Regular provider/site of care
      Yes750.11 (0.08, 0.15)
      p <0.001.
      850.15 (−0.05, 0.36)
      No52
      p <0.001.
      –––61
      p <0.001.
      –––
      Disclosed sexual orientation to a health care provider
      Yes800.11 (0.09, 0.14)
      p <0.001.
      860.03 (−0.08, 0.13)
      No58
      p <0.001.
      –––80–––
      Lifetime history of vaginal intercourse without a condom
      Yes750.06 (0.04, 0.08)
      p <0.001.
      Item not included in the model to assess receipt of a mammogram within 2 years.
      Item not included in the model to assess receipt of a mammogram within 2 years.
      No63
      p <0.001.
      –––
      Lifetime history of an STD
      Yes820.05 (0.02, 0.07)
      p <0.001.
      Item not included in the model to assess receipt of a mammogram within 2 years.
      Item not included in the model to assess receipt of a mammogram within 2 years.
      No69
      p <0.001.
      –––
      History of breast lumps or fibroids
      Yes
      Items not included in the model to assess receipt of a Pap smear within 2 years.
      Items not included in the model to assess receipt of a Pap smear within 2 years.
      920.06 (−0.06, 0.18)
      No80
      p <0.001.
      –––
      Tobacco use
      Yes64−0.04 (−0.06, −0.01)
      p <0.01,
      Item not included in the model to assess receipt of a mammogram within 2 years.
      Item not included in the model to assess receipt of a mammogram within 2 years.
      No73
      p <0.001.
      –––
      Alcohol use
      Yes
      Items not included in the model to assess receipt of a Pap smear within 2 years.
      Items not included in the model to assess receipt of a Pap smear within 2 years.
      870.04 (−0.05, 0.13)
      No79
      p <0.05,
      –––
      a Receipt of a mammogram was assessed for women aged ≥50 years only.
      legend ––– Reference categories (i.e., omitted variables);
      p <0.05,
      ∗∗ p <0.01,
      ∗∗∗ p <0.001.
      Items not included in the model to assess receipt of a Pap smear within 2 years.
      □□□ Item not included in the model to assess receipt of a mammogram within 2 years.
      legend CI, confidence interval
      In a multivariate model that included patient and provider characteristics (Table 3), we found that receipt of Pap smears within 2 years was positively associated with women who were aged ≥50, had graduate or professional school experience compared with some college or high school education, had annual incomes >$50,000, had regular providers or sites for medical care, had disclosed their sexual orientation to their health care providers, had lifetime histories of vaginal intercourse without condom use, and had lifetime histories of at least one STD. Current tobacco use was negatively associated with receiving Pap smears. Receipt of a Pap smear within 2 years was not significantly associated with race/ethnicity or size of community.
      After stratifying by education and age, the greatest disparity in rates for receipt of Pap smears within 1 year appear to be between lesbians aged <35 in all educational categories and their counterparts in the general U.S. population (Table 4). A trend appears for lesbians to have higher rates of Pap smears with older age, whereas the rates for women in the general U.S. population appear to decrease with increasing age.
      Table 4Receipt of Pap smears and mammograms within 1 year by education and age among lesbians and women in the general U.S. population
      Gallup Poll, 1997. Data provided courtesy of the College of American Pathologists and the Gallup Organization, March 5, 1998. n=1596 is the weighted base of respondents.
      Variation was measured between women of the same educational status and age:
      No college educationSome college educationGraduated college
      <35 % (n)35–49 % (n)≥50 % (n)<35 % (n)35–49 % (n)≥50 % (n)<35 % (n)35–49 % (n)≥50 % (n)
      Pap smear
      Lesbians (n=6935)37.0 (198)52.2 (180)56.1 (23)42.0 (404)55.2 (357)70.8 (34)52.1 (1,072)62.4 (1,246)70.8 (182)
      U.S. women (n=1596)70.2 (160)
      p <0.001.
      59.8 (122)45.3 (178)78.8 (146)
      p <0.001.
      74.0 (101)
      p <0.001.
      64.8 (77)76.2 (82)
      p <0.001.
      71.0 (91)
      p <0.05,
      58.8 (57)
      p <0.05,
      Mammogram
      Lesbians (n=403)63.6 (28)69.6 (39)70.7 (212)
      U.S. women (n=609)51.9 (204)65.5 (78)72.2 (70)
      a Gallup Poll, 1997. Data provided courtesy of the College of American Pathologists and the Gallup Organization, March 5, 1998. n=1596 is the weighted base of respondents.
      legend Variation was measured between women of the same educational status and age:
      p <0.05,
      ∗∗ p <0.001.

      Receipt of mammograms

      Seventy percent of all respondents aged ≥50 had mammograms during the preceding year, and 83% of women had them within 2 years (Table 2). Forty-seven percent of women aged 40 to 49 had mammograms in the past year, and 80% had them in the past 2 years. In bivariate analysis for respondents aged ≥50, women with more education, higher annual incomes, regular health care providers, histories of breast lumps or fibroids, and regular consumption of alcohol had received mammograms during the past 2 years at significantly higher rates (Table 3).
      In the multivariate model for receipt of mammograms during the past 2 years among lesbians aged ≥50, we adjusted for race, education, income, and size of residential community. However, none of the independent variables—having a regular provider, disclosure of one’s sexual orientation to a provider, history of a breast mass and alcohol use—demonstrated an independent effect (Table 3).
      Comparison with women aged ≥50 of similar education in the general U.S. population

      Gallup Poll, 1997. Data provided courtesy of the college of American Pathologists and the Gallup Organization, March 5, 1998.

      did not reveal any statistically significant differences between the two samples (Table 4). Education did not appear to have as strong an influence on receipt of mammograms for lesbians aged ≥50, whereas higher educational levels corresponded with increasing rates of screening for women of similar age in the general population.

      Discussion

      The comparison of lesbians’ rates of receipt of Pap smears with rates for American women in general might mislead some readers to believe that currently lesbians are more likely to get this preventive screening test. However, findings from the recent Gallup Poll that allowed us to compare rates after stratifying by age and education, revealed that young lesbians, especially, are at increased risk for not receiving Pap smears relative to their counterparts in the general U.S. population.

      Gallup Poll, 1997. Data provided courtesy of the college of American Pathologists and the Gallup Organization, March 5, 1998.

      Of note, participants in the Gallup Poll, a population-based survey, would be expected to include heterosexual women, lesbians, and bisexual women. Inclusion of lesbians in the Gallup Poll is unlikely to affect the reported rates because of the small proportion of lesbians estimated in the population.
      • Laumann E.O
      • Gagnon J.H
      • Michael R.T
      • Michaels S
      The Pap smear rates in our study—54% at 1 year and 71% at 2 years—are similar to rates reported from the 1984–1985 National Lesbian Health Care Survey (50% and 71%, respectively).
      • Bradford J
      • Ryan C
      Although cervical cancer screening rates in the general population do not meet the goals of Healthy People 2000 (i.e., for 95% of women aged ≥18 to have ever received Pap smears, and 85% of women aged ≥18 to have received Pap smears within 1 to 3 years),

      U.S. Department of Health and Human Services. Healthy People 2000—midcourse review and 1995 revisions, Washington, DC: U.S. Department of Health and Human Services, Public Health Service, 1995.

      the rates in the general population have increased since the mid-1980s.

      Leiman JM, Bussel ME, Collins KS, et al. Health concerns across a woman’s lifespan: The Commonwealth Fund 1998 Survey of Women’s Health. New York: The Commonwealth Fund, 1999.

      ,

      Leiman JM, Meyer JE, Rothschild N, Simon LJ. Selected facts on US women’s health. New York: The Commonwealth Fund Commission on Women’s Health, March 1997.

      However, our data suggest that younger lesbians continue to have lower rates for receipt of this important screening procedure.
      This disparity is important in light of findings that a majority of respondents had risk factors for cervical dysplasia, including vaginal intercourse without condom use during their lifetimes.
      • Marrazzo J.M
      • Koutsky L.A
      • Stine K.L
      • et al.
      Genital human papillomavirus infection in women who have sex with women.
      ,
      • Rankow E.J
      • Tessaro I
      Cervical cancer risk and Papanicolaou screening in a sample of lesbian and bisexual women.
      Elsewhere we report how a large proportion of lesbians share this risk factor with heterosexual women
      • Diamant A.L
      • Schuster M
      • McGuigan K
      • Lever J
      Lesbians’ sexual histories with men implications for taking a sexual history.
      as well as other known risk factors for cervical dysplasia, including a greater number of lifetime male sexual partners, younger age at first coitus, tobacco use, and HIV seropositivity.
      U.S. Preventive Services Task Force
      ,

      National Cancer Institute. Statement from the National Cancer Institute on the National Cancer Advisory Board recommendations on mammography. CancerNet press release March 27, 1997.

      ,
      American Medical Association
      ,
      American Academy of Family Physicians
      ,
      American College of Physicians
      Screening for cervical cancer.
      ,
      American College of Obstetricians and Gynecologists
      When health care providers make their recommendations for the frequency of screening tests for individual patients, it is important for them to recognize that risk factors for cervical dysplasia among lesbians may not be very different from those of heterosexual women.
      • Diamant A.L
      • Schuster M
      • McGuigan K
      • Lever J
      Lesbians’ sexual histories with men implications for taking a sexual history.
      Lesbians in this sample appeared to have higher rates of abnormal Pap smears than rates reported for the general U.S. female population (0.5% to 3.1%), although this finding may be confounded because the population rates are not adjusted for age and education. In addition, the rate of abnormal Pap smears in this sample may overestimate the actual rate if women in this sample had Pap smears that revealed nondysplastic changes that they reported as abnormal.
      • Appleby J
      Management of the abnormal Papanicolaou smear.
      In contrast with our findings of unequal Pap smear rates, we found that rates for receipt of mammograms within the past year for lesbians aged ≥50 were comparable to women of similar educational level and age in the general U.S. population. Within the past decade there has been a growing acceptance of the benefits of regular breast cancer screening for women aged ≥50 and an acknowledgment of the need to increase the rates for receipt of mammograms among this group.
      U.S. Preventive Services Task Force
      ,

      Fletcher SW, Black W, Harris R, Rimer BK, Shapiro S. Report of the international workshop on screening for beast cancer. J Natl Cancer Inst 1993;85:1644–56.

      ,
      • Eddy D.M
      Screening for breast cancer.
      ,

      Kerlikowske K, Grady D, Rubin SM, Sandrock C, Ernster VL. Efficacy of screening mammography: a meta-analysis. JAMA 1995;273:149–54.

      ,
      • Bertin J.E
      Disclosure of sexual orientation to one’s health care provider may be less important for obtaining a mammogram because the recommendations for breast cancer screening are not as closely tied to sexual history. No unique risk factors for breast cancer are known to exist among lesbians compared to heterosexual women of similar characteristics.
      • Solarz A.L
      However, lesbians may be more likely to have certain risk factors for breast cancer. They may be more likely to be nulliparous (as our data support); to conceive later in life, which has been shown to have some increased risk for breast cancer

      Freudenheim JL, Marshall JR, Vena JE, et al. Lactation history and breast cancer risk. Am J Epidemiol 1997;146:932–8.

      ,

      Robertson C, Primic-Zakelj M, Boyle P, Hsieh CC. Effect of parity and age at delivery on breast cancer risk in Slovenian women aged 25–54 years. Int J Cancer 1997;73:1–9.

      ,

      Cummings P, Weiss NS, McKnight B, Stanford JL. Estimating the risk of breast cancer in relation to the interval since last term pregnancy. Epidemiology 1997;8: 488–94.

      ,
      • Enger S.M
      • Ross R.K
      • Henderson B
      • Bernstein L
      Breastfeeding history, pregnancy experience and risk of breast cancer.
      ,
      • Ramon J.M
      • Escriba J.M
      • Casas I
      • et al.
      Age at first full-term pregnancy, lactation and parity and risk of breast cancer a case-control study in Spain.
      ; or to consume greater quantities of alcohol.
      • Skinner W.F
      • Otis M.D
      Drug and alcohol use among lesbian and gay people in a southern U.
      Although rates of disclosure of sexual orientation to health care providers have been reported in a few studies, the impact of disclosure has not been well studied.
      • Zeidenstein L
      Gynecological and childbearing needs of lesbians.
      ,
      • Cochran S.D
      • Mays V.M
      Disclosure of sexual preference to physicians by black lesbian and bisexual women.
      Based on the literature, some might have predicted a negative association between disclosure of sexual orientation and receipt of Pap smears because lesbians have previously reported perceptions that disclosure could have an adverse impact on their receipt of care for acute, chronic, and preventive health issues.
      • Bradford J
      • Ryan C
      ,
      • Zeidenstein L
      Gynecological and childbearing needs of lesbians.
      ,
      • Cochran S.D
      • Mays V.M
      Disclosure of sexual preference to physicians by black lesbian and bisexual women.
      ,
      • Stevens P.E
      Lesbian health care research a review of the literature from 1970 to 1990.
      Limited use of health services by lesbians has been attributed to many things, including lack of knowledge regarding the need for preventive screening tests, inadequate financial resources and health insurance coverage (e.g., lack of spousal health insurance benefits), as well as fears of discrimination and overt hostility from health care providers or resentment of provider’s assumptions of patient’s heterosexuality.
      • Denenberg R
      Report on lesbian health.
      These fears may not be unfounded; studies of health care professionals have revealed negative attitudes and beliefs regarding homosexual patients.
      • Stevens P.E
      Lesbian health care research a review of the literature from 1970 to 1990.
      ,
      • Mathews W.C
      • Booth M.W
      • Turner J.D
      • et al.
      Physicians’ attitudes toward homosexuality survey of a California county medical society.
      ,
      • Chaimowitz G.A
      Homophobia among psychiatric residents, family practice residents and psychiatric faculty.
      ,

      Kelly CE. Bringing homophobia out of the closet: antigay bias within the patient-physician relationship. The Pharos 1992;55(1):2–8.

      ,
      • Ramos M.M
      • Tellez C.M
      • Palley T.B
      • Umland B.E
      • Skipper B.J
      Attitudes of physicians practicing in New Mexico toward gay men and lesbians in the profession.
      Notwithstanding the data from these older studies, societal acceptance of lesbians and gay men has increased considerably in the past decade. This societal change has resulted in some inclusion of lesbian and gay health care issues in medical school curricula, and led us to hypothesize that the relationship between disclosure and receipt of preventive care would be positive.
      • Nardi P.M
      The globalization of the gay and lesbian socio-political movement some observations about Europe with a focus on Italy.
      ,

      It’s normal to be queer. Economist 1996;338:68–70.

      Because of recent social change, several reasons explain why the relationship between disclosure and receipt of a Pap smear might be positively associated. First, women who feel comfortable disclosing their sexual orientation may be more open about reporting their entire sexual histories, including any experience they have had with men. This information allows the physician to make appropriate recommendations for screening. Second, perhaps the lesbian patient’s underlying attitude has more to do with health promotion awareness than with sexual openness. The women who disclose their sexual orientation may also be the most proactive in terms of making sure that they receive preventive health services. Similarly, awareness of the importance of obtaining preventive screenings may encourage some women to seek out health care providers who are nondiscriminatory and nonjudgmental in their provision of health care. Consequently, these women may have higher rates of disclosure because of their perception that they have little to fear. A third explanation is based on variation in physicians’ behaviors. It may be that physicians who are more conscientious about performing proper health screenings may also be more likely to include sexual orientation when taking a history.
      Although this article presents results from the largest sample of lesbians studied to date, it did not use probability sampling; therefore, the respondents are probably not representative of all lesbians. Unfortunately, knowledge about lesbian health issues has come from studies that relied on convenience sampling because data from national probability samples have not been available. The difficulty in identifying a representative sample of all lesbians may be due in part to the hesitancy of some women to disclose their sexual orientation. However, recognition is growing among health care providers and researchers of the need to study the health seeking behaviors and health care requirements of lesbians in a systematic and generalizable manner.
      • Simkin R.J
      Lesbians face unique health care problems.
      ,
      • White J
      • Levinson W
      Primary care of lesbian patients.
      ,
      • White J
      Lesbian health care—what a primary care physician needs to know.
      ,
      • Rankow E.J
      Lesbian health issues for the primary care provider.
      ,
      • Rankow E.J
      Breast and cervical cancer among lesbians.
      ,
      • Harrison A.E
      Primary care of lesbian and gay patients educating ourselves and our students.
      Specifically, the National Academy of Sciences’ Institute of Medicine formed an expert panel that recently reported on the need to establish a research agenda to focus on the health care issues of lesbians.
      • Solarz A.L
      Magazine readership in general tends to be biased toward people with higher than average education and income,
      • Strassberg D.S
      • Lowe K
      Volunteer bias in sexuality research.
      ,
      • Crooks R
      • Baur K
      which was true of our sample. Because of their very high educational levels, the women in this study may have better understanding of the importance of preventive services, may have greater access to health care due to employment and health insurance coverage, and may be more active in seeking age-appropriate health care services. We cannot rule out some difference between older versus younger lesbians who chose to respond to the survey, which may have influenced their receipt of Pap smears and mammograms.
      In conclusion, we found that lesbians’ receipt of preventive services was significantly associated with a variety of patient and provider characteristics. The results of this study indicate a need for improved patient and provider education regarding lesbians’ receipt of Pap smears. Even among highly educated lesbians with the financial resources to pay for high-quality health care, a significant proportion fail to undergo needed screening tests. Health care providers need to understand that many lesbians are at risk for cervical dysplasia because of previous sexual relations with men and the possibility that HPV may be transmitted between women. Additionally, it is important for clinicians to provide complete and appropriate preventive health care for their lesbian patients. Further research is needed to determine why lesbians are not receiving Pap smears at the recommended rate and whether this disparity relates to their own or their providers’ perceived need for the test, to their discomfort with the pelvic exam, or whether it indicates a more general problem with access to health care including receipt of preventive services.

      Acknowledgements

      This study was supported by grants from the Centers for Disease Control and Prevention and the Lesbian Health Fund, and by the UCLA Robert Wood Johnson Clinical Scholars Program and the University of California, Los Angeles–NRSA Primary Care Fellowship. We thank Carol Edwards for programming, David E. Kanouse for assistance in survey development, Lillian Gelberg MD, MSPH, for her input on early drafts of this manuscript, and the comments of the anonymous reviewers. This work does not necessarily represent the opinions of the funding organizations or of the institutions with which the authors are affiliated.

      References

        • Andersen R.M
        Revisiting the behavioral model and access to medical care.
        J Health Soc Behav. 1995; 36: 1-10
        • Hulka B.S
        • Wheat J.R
        Patterns of utilization.
        Med Care. 1985; 23: 438-460
        • Solarz A.L
        Lesbian health. Institute of Medicine, National Academy Press, Washington, DC1999
        • Johnson S.R
        • Guenther S.M
        • Laube D
        • et al.
        Factors influencing lesbian gynecologic care.
        Am J Obstet Gynecol. 1981; 140: 20-28
        • Johnson S.R
        • Smith E.M
        • Guenther S.M
        Comparison of gynecologic health care problems between lesbians and bisexual women.
        J Reprod Med. 1987; 32: 805-811
        • Bradford J
        • Ryan C
        The National Lesbian Health Care Survey Final Report. National Lesbian and Gay Health Foundation, Washington, DC1987
        • Zeidenstein L
        Gynecological and childbearing needs of lesbians.
        J Nurse Midwifery. 1990; 35: 10-18
        • Rankow E.J
        • Tessaro I
        Cervical cancer risk and Papanicolaou screening in a sample of lesbian and bisexual women.
        J Fam Pract. 1998; 47: 139-143
        • Roberts S.J
        • Sorensen L
        Health related behaviors and cancer screening of lesbians.
        Women and Health. 1999; 28: 1-12
        • Price J.H
        • Easton A.N
        • Tellijohann S.K
        • Wallace P.B
        Perceptions of cervical cancer and Pap smear screening behavior by women’s sexual orientation.
        J Comm Health. 1996; 21: 89-105
        • Carroll N.M
        Optimal gynecologic and obstetric care for lesbians.
        Obstet Gynec. 1999; 93: 611-613
      1. Koh A. Use of preventive health behaviors by lesbian, bisexual, and heterosexual women: questionnaire survey. West J Med 2000. In press.

      2. Diamant AL, Spritzer K, Wold C, Gelberg L. The effect of sexual orientation on health behaviors, health status, and access to and use of health care: a population-based study of women. Under review.

        • Aday L.A
        • Andersen R
        A framework for the study of access to medical care.
        Health Serv Res. 1974; 9: 208-220
        • Weissman J.S
        • Stern R
        • Fielding S.L
        • et al.
        Delayed access to health care.
        Ann Intern Med. 1991; 114: 325-331
        • Aday L.A
        • Awe W.C
        Health sources utilization models.
        in: Gochman D.S Handbook of health research. Vol. 1. Determinants of health behavior personal and social. Plenum, New York1995
        • Millman M
        • Institute of Medicine Committee on Monitoring Access to Personal Health Care Services
        Access to health care in America. National Academy of Sciences. National Academy Press, Washington, DC1993
        • Lambrew J.M
        • DeFirese G.H
        • Carey T.S
        • et al.
        The effects of having a regular doctor on access to primary care.
        Med Care. 1996; 34: 138-151
        • Weissman J.S
        • Stern R
        • Fielding S.L
        • et al.
        Delayed access to health care.
        Ann Intern Med. 1991; 114: 325-331
        • Dardick L
        • Grady K.E
        Openness between gay persons and health professionals.
        Ann Intern Med. 1980; 93: 115-119
        • Smith E.M
        • Johnson S.R
        • Guenther S.M
        Health care attitudes and experiences during gynecologic care among lesbians and bisexuals.
        Am J Public Health. 1985; 75: 1086-1087
        • Cochran S.D
        • Mays V.M
        Disclosure of sexual preference to physicians by black lesbian and bisexual women.
        West J Med. 1988; 149: 616-619
        • Bybee D
        The Michigan Lesbian Health Survey. Michigan Department of Public Health, Detroit, MI1991
        • Warshafsky L
        Lesbian health needs assessment. Los Angeles Gay and Lesbian Community Center, Los Angeles, CA1992
      3. O’Hanlan K. Lesbian health and homophobia: perspectives for the treating obstetrician/gynecologist. Curr Probl Obstet Gynecol Fertil 1995; July/August:97–133.

        • Diamant A.L
        • Schuster M
        • McGuigan K
        • Lever J
        Lesbians’ sexual histories with men.
        Arch Intern Med. 1999; 159: 2730-2736
        • Nardi P.M
        The globalization of the gay and lesbian socio-political movement.
        Sociological Perspectives. 1998; 41: 567
      4. It’s normal to be queer. Economist 1996;338:68–70.

        • U.S. Preventive Services Task Force
        Guide to clinical preventive services, 2nd ed. Williams and Wilkins, Baltimore1996
      5. Centers for Disease Control and Prevention, National Center for Health Statistics. National health interview survey. NHIS health promotion/disease prevention year 2000 objectives supplement. Hyattsville, MD: Public Health Service, 1994.

        • American Cancer Society
        American Cancer Society statement on mammography guidelines. American Cancer Society, Atlanta, GA1997
      6. National Cancer Institute. Statement from the National Cancer Institute on the National Cancer Advisory Board recommendations on mammography. CancerNet press release March 27, 1997.

        • American Medical Association
        AMA guidelines for adolescent preventive services (GAPS). American Medical Association, Chicago1994
        • Ursin G
        • Ross R.K
        • Sullivan-Halley J
        • Hanisch R
        • Henderson B
        • Bernstein L
        Use of oral contraceptives and risk of breast cancer in young women.
        Breast Cancer Res Treat. 1998; 50: 175-184
      7. Van Os WA, Edelman DA, Rhemrev PE, Grant S. Oral contraceptives and breast cancer risk. Advances in contraception 1997;13:63–9.

        • Brinton L.A
        • Daling J.R
        • Liff J.M
        • et al.
        Oral contraceptives and breast cancer risk among younger women.
        J Natl Cancer Inst. 1995; 87: 827-835
        • dos Santos Silva I
        • Swerdlow A.J
        Recent trends in incidence of and mortality from breast, ovarian and endometrial cancers in England and Wales and their relation to changing fertility and oral contraceptive use.
        Br J Cancer. 1995; 72: 485-492
        • Grimes D.A
        • Economy K.E
        Primary prevention of gynecologic cancers.
        Am J Obstet Gynecol. 1995; 172: 227-235
        • Oriel K.A
        • Hartenbach E.M
        • Remington P.L
        Trends in United States ovarian cancer mortality, 1979–1995.
        Obstet Gynecol. 1999; 93: 30-33
        • Bornstein J
        • Rahat M.A
        • Abramovici H
        Etiology of cervical cancer.
        Obstet Gynecol Surv. 1995; 50: 146-154
        • Hirose K
        • Hamajima N
        • Takezaki T
        • et al.
        Smoking and dietary risk factors for cervical cancer at different age group in Japan.
        J Epidemiol. 1998; 8: 6-14
        • Smith-Warner S.A
        • Spiegelman D
        • Yaun S.S
        • et al.
        Alcohol and breast cancer in women.
        JAMA. 1998; 279: 535-540
        • Bradley K.A
        • Badrinath S
        • Bush K
        • Boyd-Wickizer J
        • Anawalt B
        Medical risks for women who drink alcohol.
        J Gen Int Med. 1998; 13: 627-639
        • Tseng M
        • Weinberg C.R
        • Umbach D.M
        • Longnecker M.P
        Calculation of population attributable risk for alcohol and breast cancer (United States).
        Cancer Causes Control. 1999; 10: 119-123
      8. Gallup Poll, 1997. Data provided courtesy of the college of American Pathologists and the Gallup Organization, March 5, 1998.

      9. SAS Institute, Inc. SAS 6.12. Cary, NC: SAS Institute Inc., 1990.

        • Laumann E.O
        • Gagnon J.H
        • Michael R.T
        • Michaels S
        The social organization of sexuality sexual practices in the United States. University of Chicago Press, Chicago1994: 295
      10. U.S. Department of Health and Human Services. Healthy People 2000—midcourse review and 1995 revisions, Washington, DC: U.S. Department of Health and Human Services, Public Health Service, 1995.

      11. Leiman JM, Bussel ME, Collins KS, et al. Health concerns across a woman’s lifespan: The Commonwealth Fund 1998 Survey of Women’s Health. New York: The Commonwealth Fund, 1999.

      12. Leiman JM, Meyer JE, Rothschild N, Simon LJ. Selected facts on US women’s health. New York: The Commonwealth Fund Commission on Women’s Health, March 1997.

        • Marrazzo J.M
        • Koutsky L.A
        • Stine K.L
        • et al.
        Genital human papillomavirus infection in women who have sex with women.
        J Infect Dis. 1998; 8: 1604-1609
        • American Academy of Family Physicians
        Age charts for periodic health examination. American Academy of Family Physicians, Kansas City, MO1994 (reprint no. 510)
        • American College of Physicians
        Screening for cervical cancer.
        in: Eddy D.M Common screening tests. American College of Physicians, Philadelphia1991: 413-414
        • American College of Obstetricians and Gynecologists
        Recommendations on frequency of Pap test screening. Committee Opinion no. 152. American College of Obstetricians and Gynecologists, Washington, DC1995
        • Appleby J
        Management of the abnormal Papanicolaou smear.
        Med Clin North Am. 1995; 79: 345-358
      13. Fletcher SW, Black W, Harris R, Rimer BK, Shapiro S. Report of the international workshop on screening for beast cancer. J Natl Cancer Inst 1993;85:1644–56.

        • Eddy D.M
        Screening for breast cancer.
        Ann Intern Med. 1989; 111: 389-399
      14. Kerlikowske K, Grady D, Rubin SM, Sandrock C, Ernster VL. Efficacy of screening mammography: a meta-analysis. JAMA 1995;273:149–54.

        • Bertin J.E
        Briefing paper routine mammography screening for women ages 40–49. The Commonwealth Fund Commission on Women’s Health, New York1994: 7-15
      15. Freudenheim JL, Marshall JR, Vena JE, et al. Lactation history and breast cancer risk. Am J Epidemiol 1997;146:932–8.

      16. Robertson C, Primic-Zakelj M, Boyle P, Hsieh CC. Effect of parity and age at delivery on breast cancer risk in Slovenian women aged 25–54 years. Int J Cancer 1997;73:1–9.

      17. Cummings P, Weiss NS, McKnight B, Stanford JL. Estimating the risk of breast cancer in relation to the interval since last term pregnancy. Epidemiology 1997;8: 488–94.

        • Enger S.M
        • Ross R.K
        • Henderson B
        • Bernstein L
        Breastfeeding history, pregnancy experience and risk of breast cancer.
        Br J Cancer. 1997; 76: 118-123
        • Ramon J.M
        • Escriba J.M
        • Casas I
        • et al.
        Age at first full-term pregnancy, lactation and parity and risk of breast cancer.
        Eur J Epidemiol. 1996; 12: 449-453
        • Skinner W.F
        • Otis M.D
        Drug and alcohol use among lesbian and gay people in a southern U.
        S. sample: epidemiological, comparative, and methodological findings from the Trilogy Project. J Homosex. 1996; 30: 59-91
        • Stevens P.E
        Lesbian health care research.
        Health Women Int. 1992; 13: 91-120
        • Denenberg R
        Report on lesbian health.
        Womens Health Int. 1995; 5: 81-91
        • Mathews W.C
        • Booth M.W
        • Turner J.D
        • et al.
        Physicians’ attitudes toward homosexuality.
        West J Med. 1986; 144: 106-110
        • Chaimowitz G.A
        Homophobia among psychiatric residents, family practice residents and psychiatric faculty.
        Can J Psychiatry. 1991; 36: 206-209
      18. Kelly CE. Bringing homophobia out of the closet: antigay bias within the patient-physician relationship. The Pharos 1992;55(1):2–8.

        • Ramos M.M
        • Tellez C.M
        • Palley T.B
        • Umland B.E
        • Skipper B.J
        Attitudes of physicians practicing in New Mexico toward gay men and lesbians in the profession.
        Acad Med. 1998; 73: 436-438
        • Simkin R.J
        Lesbians face unique health care problems.
        Can Med Assoc J. 1991; 145: 1623
        • White J
        • Levinson W
        Primary care of lesbian patients.
        J Gen Intern Med. 1993; 8: 41-47
        • White J
        Lesbian health care—what a primary care physician needs to know.
        West J Med. 1995; 162: 463-466
        • Rankow E.J
        Lesbian health issues for the primary care provider.
        J Fam Pract. 1995; 40: 486-493
        • Rankow E.J
        Breast and cervical cancer among lesbians.
        Womens Health Issues. 1995; 5: 123-129
        • Harrison A.E
        Primary care of lesbian and gay patients.
        Fam Med. 1996; 28: 10-23
        • Strassberg D.S
        • Lowe K
        Volunteer bias in sexuality research.
        Arch Sex Behav. 1995; 24: 369-382
        • Crooks R
        • Baur K
        Sex research methods and problems. Our Sexuality, 7th ed. Brooks/Cole, Pacific Grove, CA1999: 37