In a subcohort of the ALSPAC study in whom detailed early postnatal growth data were collected (n = 914), mother's age at menarche was inversely related to her offspring's infancy weight gain (p < 0.001) and height gain (p < 0.001) between birth and 2 y (adjusted for sex, gestational age, parity, mother's BMI, and breast-feeding status at age 4 mo [Table 2]). These associations were similar in boys and girls (p-value for interaction = 0.8), and in breast-fed and formula milk–fed infants (p-interaction = 0.9). However, mother's age at menarche was unrelated to her offspring's size at birth or later childhood growth rates (between 2–9 y) (Table 2). Figure 2 shows the contrasting early growth patterns between children in the earliest and oldest quintiles for mother's age at menarche.
