Fertility Epidemiology Studies

Fertility Epidemiology Studies (FES) conducts epidemiologic research and surveillance on fertility and other reproductive health issues throughout the lifespan including contraceptive safety and efficacy, prevention of unintended pregnancy, menopause, hysterectomy, and adverse reproductive sequelae of childhood abuse and household dysfunction.

CDC's Division of Reproductive Health has a long history of conducting important epidemiologic studies on the safety and effectiveness of contraceptive methods, which have had a lasting impact on contraceptive practice. The Collaborative Review of Sterilization (CREST) began in 1978 and followed women with tubal sterilization for up to 14 years, yielding information about the safety and effectiveness of one of the most common methods of contraception in the United States. Findings from the CREST study continue to provide new information about female sterilization, including the impact of marital conflict on later regret and no evidence of negative impact of tubal sterilization on subsequent sexual function. The Cancer and Steroid Hormone (CASH) study, conducted in the early 1980s, found that combined oral contraceptives did not increase the risk of breast cancer in the study population and reduced the risk of endometrial and ovarian cancers. Analyses using CASH data continue—survival after breast, ovarian, and endometrial cancers in relation to use of oral contraceptives, estrogen replacement therapy, and reproductive, lifestyle, and family history factors. CREST and CASH were followed by the Women’s CARE Study, in which findings showed that, overall, oral contraceptive use did not increase the risk of breast cancer in this study population of women aged 35–64 years. These findings are expected to provide important guidance for women and health care providers about the association between oral contraceptives and breast cancer. Numerous secondary analyses are underway from Women’s CARE.

While much of the CDC’s work is focused domestically, there is also a strong international component, including a partnership with officials in the Russian Ministry of Health, which issued new national congenital syphilis prevention guidelines as a consequence of the collaborative study on congenital syphilis in the Russian Federation. This work has strengthened progress towards implementing international guidelines for prevention of maternal to child transmission of HIV.

CDC provides the evidence base for WHO’s family planning guidelines, Medical Eligibility Criteria for Contraceptive Use and Selected Practice Recommendations for Contraceptive Use. These guidelines, currently available in eight languages, have influenced family planning practices in more than 50 countries, and been fully incorporated into the most widely used family planning guides around the world, including the United States. The CDC's staff use the Continuous Identification of Research Evidence (CIRE) system to identify and critically appraise new evidence as it becomes available, to ensure that WHO’s family planning guidelines remain current and based on the best available evidence. CDC has adapted WHO’S Family Planning Guidelines for use in the United States. In addition, the CDC conducts regional Reproductive Health Training workshops, building capacity for applying epidemiologic method to reproductive health issues internationally.