Menstrual cycle characteristics and fecundability in a North American preconception cohort

Abstract

Purpose To evaluate the association between menstrual cycle characteristics in early life and adulthood and fecundability. Methods Pregnancy Study Online (PRESTO) is an internet-based preconception cohort study of pregnancy planners from the United States and Canada. During the preconception period, we enrolled 2,189 female pregnancy planners age 21–45 years who had been attempting conception for ≤6 cycles. Women self-reported menstrual cycle characteristics via an online baseline questionnaire, and pregnancy status was ascertained through bi-monthly follow-up questionnaires. Proportional probabilities models were used to estimate fecundability ratios (FRs) and 95% confidence intervals (CIs), adjusting for potential confounders. Results Compared with usual menstrual cycle lengths of 27–29 days, cycle lengths of <25 (FR=0.81, 95% CI: 0.54–1.22) and 25–26 days (FR=0.92, 95% CI: 0.75–1.14) were associated with reduced fecundability. Compared with women who reached menarche at age 12–13 years, those who reached menarche at <12 years had reduced fecundability (FR=0.87, 95% CI: 0.76–0.99). Women whose cycles never regularized after menarche (FR=0.93, 95% CI: 0.81, 1.06) had slightly reduced fecundability compared with women whose cycles regularized within 2 years of menarche. Bleed length and heaviness of bleeding were not appreciably associated with fecundability. Conclusions Menstrual cycle characteristics, specifically cycle length and age at menarche, may act as markers of fertility potential among pregnancy planners.

Pregravid contraceptive use and fecundability: prospective cohort study

“…This study had several limitations. First, some misclassification of cycles was likely because our calculation of time-to-pregnancy relied on reported length of the menstrual cycle 36 and date of the last menstrual period. 11 Misclassification could also have arisen if participants interpreted the question, “Did you wait a few months after stopping hormonal contraception before trying to get pregnant?” as asking about two or three months specifically.…”

Mating Effort Predicts Human Menstrual Cycle Frequency

“…Finally, it should be noted that we asked women to self-report the length and regularity of their cycles. Although multiple studies have successfully used self-reporting to measure estimated cycle length (e.g., Barron et al, 2008; Rowland et al, 2002; Wesselink et al, 2016), others find that such methods are less accurate for those with very long or very short cycle lengths, as well as those reporting high variability in cycle lengths (Small, Manatunga, & Marcus, 2007). Future research would benefit from validating self-reported cycle characteristics with more objective measures, such as period tracking phone applications or hormone analysis.…”

“…Guided by these insights, we sought to examine whether conditions that favor investment in mating effort predict shorter, more regular cycles. Total fecundity varies, in large part, by the length and frequency of women’s cycles, with shorter, more regular cycles corresponding to increased fecundity (Jensen et al, 1999; Wesselink et al, 2016; Zhang et al, 2017). Such a relationship might exist because greater cycle frequency provides more opportunities for conception.…”

Relationship between age at menarche and chromosome numerical abnormalities in chorionic villus among missed abortions: A cross‐sectional study of 459 women in China

“…4 Previous studies showed that menstrual cycle and age at menarche can be used as dynamic indicators to access fertility. 5 Studies have shown that early menarche can reduce hormones concentration secreted by ovaries and influence ovarian reserve function, which are closely related to the occurrence of preterm birth and abortion. 6,7 Previous studies paid more attention to the relationship between the patient age and embryonic chromosome abnormality and they believed that pregnant women age is closely related to the chromosome numerical abnormalities.…”