Trajectories of maternal leisure-time physical activity and sedentary behavior during adolescence to young adulthood and offspring birthweight

Abstract

PurposeThe objectives of the study were to determine the extent to which trajectories of maternal preconception leisure-time physical activity (LTPA) and leisure-time sedentary behavior (LTSB) during adolescence and young adulthood are associated with offspring birth weight (BW) and to test if these associations differ by offspring sex or maternal pre-pregnancy overweight–obese status. MethodsParticipants with one or more birth (n = 1408) were identified from the National Longitudinal Study of Adolescent to Adult Health. Group-based trajectory modeling was used to characterize trajectories of LTPA (frequency/week) and LTSB (hours/week) which were measured, on average, over 7 years between age 15 and 22 years. Weighted regression and Wald tests were used to estimate and test mean differences and odds ratios for BW, small for gestational age, and large for gestational age (LGA). ResultsThree trajectories were identified for LTPA and five for LTSB. Associations differed by offspring sex for continuous BW and LGA (interaction P = .10 and .008, respectively). Among female offspring, participants with high followed by decreasing LTPA delivered offspring with 90 g greater BW (95% confidence interval [CI]: −4 to 184) and 72% greater risk of LGA (95% CI: 0.94–3.14), compared with participants with low LTPA. Among male offspring, LTPA patterns were not associated with BW. A pattern of high then decreasing LTPA among normal weight, but not overweight–obese women, was associated with 2.03 times greater risk of LGA (95% CI: 1.06–3.88). LTSB trajectories were not associated with BW. ConclusionsAssociations of preconception trajectories of LTPA with offspring BW may differ by offspring sex and maternal pre-pregnancy overweight–obese status.