American Journal of Epidemiology, 165(9), 1088-1095, 2007
Abstract
Time to pregnancy, typically defined as the number of menstrual cycles required to achieve a clinical pregnancy, is widely used as a measure of couple fecundity in epidemiologic studies. Time to pregnancy studies seldom utilize detailed data on the timing and frequency of sexual intercourse and the timing of ovulation. However, the simulated models in this paper illustrate that intercourse behavior can have a large impact on time to pregnancy and, likewise, on fecundability ratios, especially under conditions of low intercourse frequency or low fecundity. Because intercourse patterns in the menstrual cycles may vary substantially among groups, it is important to consider the effects of sexual behavior. Where relevant and feasible, an assessment should be made of the timing and frequency of intercourse relative to ovulation. Day-specific probabilities of pregnancy can be used to account for the effects of intercourse patterns. Depending on the research hypothesis, intercourse patterns may be considered as a potential confounder, mediator, or outcome.
Topics
sexual intercourse frequency time to pregnancy studies, intercourse timing ovulation fecundability ratio, Dunson Stanford intercourse patterns fertility, day-specific probability of pregnancy intercourse timing, fecundability confounding intercourse behavior, time to pregnancy epidemiologic study design, low intercourse frequency effect on fecundity measurement, menstrual cycle intercourse timing fertility awareness, simulation model time to pregnancy fecundability, intercourse pattern confounder mediator pregnancy outcome, couple fecundity measurement epidemiology methodology
PMID 17289774 17289774 DOI 10.1093/aje/kwk111 10.1093/aje/kwk111 Dunson et al. 2007, Dunson 2007
Cite this article
Stanford, J. B., & Dunson, D. B. (2007). Effects of sexual intercourse patterns in time to pregnancy studies. American journal of epidemiology, 165(9), 1088-1095. https://doi.org/10.1093/aje/kwk111
Stanford JB, Dunson DB. Effects of sexual intercourse patterns in time to pregnancy studies. Am J Epidemiol. 2007;165(9):1088-1095. doi:10.1093/aje/kwk111
Stanford, J. B., and D. B. Dunson. "Effects of sexual intercourse patterns in time to pregnancy studies." American journal of epidemiology, vol. 165, no. 9, 2007, pp. 1088-1095.
Keywords
Coitus, Confounding Factors, Epidemiologic, Female, Fertility, Fertilization, Humans, Menstrual Cycle, Models, Biological, Ovulation, Pilot Projects, Pregnancy, Probability, Sexual Behavior/statistics & Numerical Data, Time Factors
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