Abstract and Introduction
Abstract
Context: Prepubertal obesity is a well-established predictor of earlier pubertal onset, which is itself a risk factor for poor health and well-being. Identifying specific patterns of weight gain in early life may help explain differential risk for earlier pubertal onset.
Objective: The objective of the study was to examine patterns of weight gain across infancy and early childhood in relation to pubertal onset outcomes.
Design, Setting, and Participants: Participants were 426 girls in the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development, a longitudinal birth cohort of children and their families followed between birth and adolescence.
Main Outcome Measures: Three pubertal onset outcomes were examined, including age at menarche and ages at Tanner stage II for dimensions of breast and pubic hair development.
Results: In infancy (birth to 15 months), greater percent weight gain and higher birthweight predicted earlier pubertal onset for all outcomes (Ps < 0.05). In early childhood (24 months to grade 1), body mass index (BMI) trajectories reflecting BMI values that were persistently high or changed from low to high over time (vs BMI values that were stable at median or low levels), predicted younger ages at menarche and the onset of breast (Ps < 0.05), but not pubic hair (Ps > 0.05), development. All associations were independent of breastfeeding, maternal menarcheal age, and race/ethnicity.
Conclusions: Distinct patterns of early life weight gain predict differential risk for earlier onset puberty. Focusing on these patterns for earlier and more targeted intervention may help lessen life course linkages between prepubertal obesity, accelerated pubertal development, and negative postpubertal outcomes.
Introduction
Childhood obesity in girls is a well-established predictor of earlier pubertal onset,[1,2] which is itself a risk factor for type 2 diabetes, cardiovascular disease, breast cancer, and early mortality[3–7] and for a variety of poor socioemotional (eg, depression)[8] and behavioral (eg, lower academic achievement)[9] outcomes. However, research has been more limited regarding early life patterns of weight gain that may have differential effects on pubertal development. If such patterns are identified, earlier and more targeted intervention may be possible to help break life course linkages between prepubertal obesity, accelerated pubertal development, and negative postpubertal outcomes.
Two relevant constructs pertain to rates of weight gain in infancy and trajectories of body mass index (BMI) changes in early childhood. In prior studies, "high-risk" patterns have been identified describing rapid or excess weight gain in the first months of life as well as specific patterns of BMI changes that are persistently high or shift from low to high over time.[10–14] These patterns, in turn, have been linked to subsequent risk for obesity and cardiometabolic diseases in adulthood.[15–18] With respect to pubertal development, greater weight gain, especially in infancy, has also been shown to predict earlier pubertal onset.[19–23] However, no studies, to our knowledge, have attempted to link distinct trajectories of BMI changes over the prepubertal period[10] to differential risk for earlier pubertal onset. The current study extends this work by considering both weight gain in infancy and trajectories of BMI changes in early childhood. This integrated approach may provide new insights into the developmental pathways through which such exposures shape long-term health and well-being.
The current study included 426 girls from the landmark National Institute of Child Health and Human Development (NICHD) Study of Early Child Care and Youth Development (SECCYD), a longitudinal investigation of health and development in children. The current study sought to extend prior work in this same sample[10] by examining early life patterns of weight gain in relation to pubertal onset outcomes: age at menarche and ages at Tanner stage (TS) II for dimensions of breast and pubic hair development, marking the initiation of gonadarche and adrenarche, respectively. The study objectives were 2-fold: (1) to examine percent weight gain between birth and age 15 months, adjusted for gestational age and birthweight, in relation to pubertal onset outcomes; and (2) to characterize trajectories of BMI changes between age 24 months and grade 1 in relation to pubertal onset outcomes. High-risk patterns of weight gain, reflecting greater weight gain in infancy and persistently high BMI values or changes in BMI values from low to high over early childhood (vs stable BMI values at median and low levels), were hypothesized to predict earlier pubertal onset, according to all 3 pubertal timing indicators.
J Endo Soc. 2021;5(12) © 2021 Endocrine Society
