Mother’s earlier menarche tied to child’s earlier puberty

There appears to be a link between a mother’s age at menarche (AAM) and pubertal timing in her children, a recent China study has shown. In particular, an earlier AAM also hastens puberty, corresponding to earlier menarche in girls and first ejaculation in boys.

The study included 1,198 children (mean age, 8.59±1.20 years; 670 boys) who were examined half-yearly from April 2014 to June 2019. Maternal AAM, along with other parental characteristics, were collected via a questionnaire at baseline.

Mean maternal AAM was 13.68 years, which was significantly later than that in their daughters, who experienced menarche at an average age of 11.71 years (p<0.001).

When taken as a dichotomous variable, early maternal AAM (≤13 years of age) emerged as a significant factor for their daughters’ earlier menarche (hazard ratio [HR], 1.366, 95 percent confidence interval [CI], 1.099–1.698; p<0.01) and pubic hair development as assessed by the Tanner criteria (HR, 1.229, 95 percent CI, 1.006–1.500; p<0.05).

A similar effect was reported when maternal AAM was considered as a continuous variable (HR per year, 0.905, 95 percent CI, 0.839–0.977; p<0.05).

Maternal AAM also impacted their sons’ time to first ejaculation, but only as a continuous variable (HR, 0.894, 95 percent CI, 0.828–0.965; p<0.01). Taking maternal AAM as a dichotomous factor did not yield statistical interactions with any pubertal measures in boys but was borderline significant for first ejaculation and genital development.

These risk estimates were obtained using Cox regression analysis, adjusted for the children’s body mass index z-scores, socioeconomic factors, and other variables that tested significant in simpler models. Unadjusted models revealed a stronger impact of maternal AAM on offspring pubertal timing.