Date Published: April 11, 2018
Publisher: Oxford University Press
Author(s): Rebecca B Lawn, Debbie A Lawlor, Abigail Fraser.
Earlier puberty and menarche are associated with adverse health outcomes. Reported associations of maternal adiposity with daughter’s age at menarche are inconsistent. We examined associations between maternal prepregnancy body mass index (BMI; weight (kg)/height (m)2) and gestational weight gain (GWG) and daughter’s ages at menarche (n = 3,935 mother-offspring pairs), pubarche (Tanner stage 2 for pubic hair) (n = 2,942 pairs), and thelarche (Tanner stage 2 for breast development) (n = 2,942 pairs) in the Avon Longitudinal Study of Parents and Children, a prospective United Kingdom pregnancy cohort study (baseline 1991–1992). During a follow-up period of up to 17 years (1991–2008), mean menarcheal age was 12.6 (standard deviation, 1.2) years. Both maternal prepregnancy BMI and GWG were inversely associated with daughter’s age at menarche after adjustment for maternal age, parity, socioeconomic status, smoking, maternal menarcheal age, and ethnicity (mean differences were −0.34 months (95% confidence interval: −0.45, −0.22) per BMI unit and −0.17 months (95% confidence interval: −0.26, −0.07) per kg, respectively). Associations remained unchanged after adjustment for birth weight and gestational age but were attenuated to the null when results were adjusted for daughter’s prepubertal BMI. Similar results were found for ages at pubarche and thelarche. These findings indicate that greater prepregnancy BMI and GWG are associated with earlier puberty in daughters and that these associations are mediated by daughters’ prepubertal BMIs.
Mean age at menarche in the ALSPAC girls was 12.6 (standard deviation (SD), 1.2) years. Early menarche (younger menarcheal age) was less than 11.5 years (1 SD below the mean; 15.6% of the sample). Late menarche (older menarcheal age) was more than 13.8 years (1 SD above the mean; 16.4% of the sample). Mean ages at thelarche and pubarche were 10.15 (SD, 0.03) years and 10.74 (SD, 0.03) years, respectively. The distributions of variables were similar between all singleton female offspring in ALSPAC and the observed and imputed data for eligible participants (see Web Tables 1 and 2).
In this prospective study of mother-daughter pairs from ALSPAC, we found inverse linear associations between maternal prepregnancy BMI and GWG and daughter’s ages at menarche, thelarche, and pubarche after adjustment for potential confounders, including maternal menarcheal age. This pattern of inverse associations was consistent when BMI, GWG, and menarcheal age were assessed as continuous variables and when they were all assessed as categorical variables. These associations were mediated, though not entirely, by daughter’s own prepubertal BMI.