The fertility experiences study: the complexities of infertility research, treatment approaches, and outcomes

Infertility is traditionally defined as failure to achieve pregnancy after 12 or more months of regular unprotected intercourse; an estimated 10-15% of women experience infertility at some point in their reproductive life. The majority of infertility research has been focused on couples actively seeking treatment in specialty clinics, overlooking individuals who are infertile but not seeking medical specialty treatment. This dissertation uses data from the Fertility Experiences to examine the complexities of infertility research, treatment and interventions, and outcomes. Aim 1 compares approaches to collecting information about pregnancy attempt duration and identifies predictors of misestimating time at risk for pregnancy when assessing duration using a single question compared to discrete date event histories. Aim 2 provides information on the use of interventions to enhance fertility over the course of the reproductive life. Aim 3 examines the association between infertility treatment (ovulation stimulation, intrauterine insemination (IUI), and in-vitro fertilization (IVF)) used during the cycle of conception and preterm birth (<37 weeks completed gestation) using subfertile women who conceived spontaneously, without medical treatment, as controls. Aim one found that two-thirds of women substantially misestimated their biological time at risk for pregnancy when asked a single question. Detailed attempt histories, capturing specific dates, can provide a more nuanced assessment of biological time at risk of pregnancy, duration of intentional pregnancy attempt, and specifically the number of cycles where fertility focused intercourse is being used to ensure appropriately timed intercourse. Aim two found that women commonly use both medical and nonmedical interventions while trying to conceive. Primary care clinicians and fertility specialists should assume that nearly all their patients are using some type of nonmedical intervention and should take a full history that includes assessment of behavioral changes and complementary and alternative medicine. Aim three found that all fertility treatments (ovulation drugs, IUI, and IVF) were associated with a higher incidence of preterm birth, predominantly related to multiple gestation births. The findings support the use of treatment protocols that maximize singleton gestation. In addition, the findings highlight the increased risk of preterm birth in pregnancies conceived using any medical fertility treatment, not just IVF.