Reproductive history shows no robust association with age at natural menopause

A cross-sectional study published in Menopause examined whether pregnancy and live-birth delivery counts were associated with age at natural menopause. Researchers used NHANES data from 1999 to March 2020, including women aged 45 years or older whose natural menopause occurred between ages 30 and 59. Survey-weighted analyses included 7,047 women for parity and 7,058 for gravidity, with adjustment for demographic, socioeconomic, and behavioral factors.

Women with three to four pregnancies, compared with none, had menopause an estimated 0.62 years later in the primary model (95% CI, 0.02–1.23; nominal P = 0.043). However, this association was not significant after false discovery rate correction (q = 0.17). No categorical or continuous parity or gravidity comparison remained significant after correction. Apparent nonlinear associations weakened after covariate adjustment, and no prespecified interaction was significant. A derived measure of non-live-birth pregnancies showed no stable descriptive pattern.

The findings do not support a robust nonlinear relationship or a simple model in which accumulating pregnancies delays menopause by suppressing ovulation. They also do not establish that reproductive history has no relationship with menopausal timing. The cross-sectional design cannot establish causality, menopausal age was self-reported, and the sample was restricted to women with confirmed natural menopause within the specified age range.