Abstract
Objectives
Saturated fatty acids (SFAs), of both exogenous and endogenous origins, have been implicated in fetal development and pregnancy complications. Thus, it is essential to identify modifiable factors related to SFAs besides dietary intakes. Physical activity (PA) plays an important role in metabolism of SFAs, but the associations of PA with individual SFAs during pregnancy are unknown. The objective of this study is to examine the associations of PA with total and individual SFAs during pregnancy.
Methods
Study participants are 321 women from a nested case-control study for gestational diabetes mellitus within the prospective NICHD Fetal Growth Studies-Singletons (FGS). Individual plasma phospholipid SFAs were measured at the baseline (10–14 gestational weeks [GW]), and the follow-up visits (15–26, 23–31, and 33–39 GW). PA was assessed via the Pregnancy PA Questionnaire at each visit. The associations of total PA (metabolic equivalent hours per week) quartile with maternal phospholipid SFAs were estimated by linear regression models at baseline, and generalized estimation equations (GEEs) which account for repeated measurements at follow-up visits. Resampling weights were applied to represent the entire FGS. Models were adjusted for age, race, parity, education, marital status, smoking, alcohol use, mother born in US, pre-pregnancy Body Mass Index, and Healthy Eating Index.
Results
Cross the follow-up visits, compared to the lowest quartile of PA, women in the highest quartile had higher total SFAs (Q4 vs. Q1: β = 0.82; 95% CI: 0.12 to 1.52; P-trend: 0.02). When separated by even or odd-chain SFAs, the positive association was only observed between PA and even-chain SFAs (Q4 vs. Q1: β = 0.81; 95% CI: 0.12 to 1.50; P-trend: 0.03). No association was observed for individual SFAs cross the follow-up visits. Also, PA was not associated with SFAs at baseline.
Conclusions
Our finding suggested that PA is positively associated with the maternal even-chain SFAs of both endogenous and exogenous origins, but not with odd-chain SFAs in the second and third trimesters. This finding is novel and warrants the confirmation by future studies.
Funding Sources
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)/National Institutes of Health (NIH).
105: The NICHD Fetal Growth Studies: Development of a contemporary formula for estimating gestational age from ultrasound fetal biometrics
