Mother’s age at menarche and offspring size

OBJECTIVE: An individual’s growth trajectory is, at least in part, inherited. Mother’s early age at menarche has been associated with taller offspring height and greater body mass index (BMI) at age 9 years, suggesting that mother’s age at menarche may be an intergenerational marker of growth. We examined the association between mother’s age at menarche and childhood size at birth, and at the ages 1, 3, 4, 7, and 8 years in the Collaborative Perinatal Project (CPP). SUBJECTS: We examined 128,636 measurements from 31,474 Black and White children. We transformed the original measurements into z-scores. Child size was examined in mixed models, adjusted for center, child sex, race, socioeconomic index, child’s exact age at measurement (in months), mother's age at recruitment and, depending on which measure was the outcome in the specific model, mother's height, pre-pregnancy weight, or BMI. RESULTS: Compared with children whose mother had menarche at age 15 or later, children whose mothers had age at menarche before age 12 were taller from age 1 and had higher BMI at ages 7 and 8 (0.17 and 0.19 z, respecively). CONCLUSIONS: Mother’s age at menarche is a modest predictor of their children’s growth trajectory. The mechanism is likely to be heritable, although other explanations are possible.