Quality of early family relationships and the timing and tempo of puberty: effects depend on biological sensitivity to context

Abstract

Guided by evolutionary-developmental theories of biological sensitivity to context and reproductive development, the current research examined the interactive effects of early family environments and psychobiologic reactivity to stress on the subsequent timing and tempo of puberty. As predicted by the theory, among children displaying heightened biological sensitivity to context (i.e., higher stress reactivity), higher quality parent-child relationships forecast slower initial pubertal tempo and later pubertal timing, whereas lower quality parent-child relationships forecast the opposite pattern. No such effects emerged among less context-sensitive children. Whereas sympathetic nervous system reactivity moderated the effects of parent-child relationships on both breast/genital and pubic hair development, adrenocortical activation only moderated the effect on pubic hair development. The current results build on previous research documenting what family contexts predict variation in pubertal timing by demonstrating for whom those contexts matter. In addition, the authors advance a new methodological approach for assessing pubertal tempo using piecewise growth curve analysis.

Figure 1

Scatterplot of relation between age and Tanner stage (as indexed by the integrative puberty composite) in girls and boys; pubertal maturation across the adolescent transition is highly variable and pubertal tempo appears nonlinear. Lines represent Lowess (locally weighted scatterplot smoothing) fraction curves fit to 50 data points. Lowess curves fit simple models to small subsets of the data, allowing different curves to be fit as the data builds up, point by point. The data is smoothed to fit 50 data points at a time until all 427 data points are modeled..

Figure 2

Variation in initial and subsequent pubertal tempo (based on integrative puberty composite) as a function of sympathetic nervous system (SNS) reactivity and Parental Supportiveness, controlling for sex. High versus low Parental Supportiveness only distinguishes pubertal tempo and timing in adolescents with high SNS reactivity.

Figure 3

Variation in initial and subsequent tempo of pubic hair development as a function of cortisol reactivity and Parental Supportiveness, controlling for sex. High versus low Parental Supportiveness only distinguishes tempo and timing of pubic hair development in adolescents with high cortisol responsivity.