(OR12-06-23) Longitudinal Associations Between Maternal Gestational Weight and Physical Growth at Birth, Mid-Childhood and Early Adolescence: A Birth Cohort

Objectives: To examine the association between maternal adiposity during pregnancy and offspring physical growth, and to explore whether this relationship has changed over time.

Methods: We used a birth cohort data from a randomized controlled trial of antenatal micronutrient supplementation in rural western China (ISRCTN08850194). Maternal weight and height were collected during the first, second and third trimester, and weekly weight gains during second and third trimester were calculated and classified following the IOM-2009 guidelines. Offspring length/height and weight were standardly assessed at birth, mid-childhood (age 7-10 years) and early adolescence (age 10-14 years), which were then converted into z scores (BAZ and HAZ) using the INTERGROWTH-21st and WHO growth standards, respectively. We conducted generalized linear models to examine the associations of maternal weight status during pregnancy with BAZ and HAZ at birth, mid-childhood and early adolescence, respectively, with adjustments for common covariables.

Results: A total of 586 mother-offspring pairs were analyzed and most are boys (60%). Per kg/m² increase of maternal BMI during first trimester was associated with offspring higher BAZ. The adjusted mean differences (aMD) were 0.06 (95% Confidence Interval [CI] -0.004, 0.12) at birth, 0.07 (95% CI 0.03, 0.11) at mid-childhood, and 0.11 (95% CI 0.06, 0.17) at early adolescence. In addition, maternal excessive weight gain during second and third trimester was associated with higher HAZ at birth, mid-childhood and early adolescence. The corresponding aMD was 0.15 (95% CI -0.24, 0.54), 0.27 (95% CI 0.002, 0.55) and 0.48 (95% CI 0.21, 0.75), respectively.

Conclusions: Maternal adiposity during pregnancy had long-lasting impacts on offspring BAZ and linear growth, and the association strength tended to become stronger as they grow older.

Funding Sources: This work was supported by the National Natural Science Foundation of China (grant 81872633 to LZ and 82103867 to ZZ), China Postdoctoral Science Foundation (grant 2021M702578 to ZZ).