Maternal Leisure Time Physical Activity and Pregnancy Complications

Abstract

PURPOSE: To investigate associations of pre-pregnancy and early pregnancy leisure time physical activity with pregnancy complications, and to examine whether these associations are modified by pre-pregnancy overweight/obese status. METHODS: Participants (N=3310) of the Omega study, a pregnancy cohort study, reported LTPA duration (hours/week) and energy expenditure (MET-hours/week) in the year before pregnancy (ppLTPA) and in early pregnancy (epLTPA) at 15 weeks gestation. Diagnoses of gestational diabetes mellitus (GDM) and pregnancy induced hypertension or preeclampsia (PIH/PE) were abstracted from medical records. Poisson regression models were used to determine relative risks of pregnancy complications across quartiles of duration and energy expenditure of ppLTPA or epLTPA. Stratified analysis and interaction terms were used to assess effect modification by pre-pregnancy body mass index (BMI, normal: 18.5-24.9 kg/m2 or overweight/obese: ≥25 kg/m2). RESULTS: The 25th, 50th, 75th percentiles for ppLTPA duration were 1.94, 3.98, 6.63 hours/week and 0, 2.63, 5.50 hours/week for epLTPA duration. ppLTPA was associated with decreased risk of GDM overall and among women with normal pre-pregnancy BMI. Each quartile increase in ppLTPA duration was associated with 14% (RR=0.86; 95% CI: 0.75-0.99) and 18% (RR=0.82; 95% CI: 0.67-0.99) lower risk of GDM overall and among women with normal pre-pregnancy BMI, respectively. epLTPA was associated with decreased risk of GDM overall and among women with overweight/obese pre-pregnancy BMI. Each quartile increase in epLTPA duration was associated with 13% (RR=0.87; 95% CI: 0.75-1.00) and 18% (RR=0.82; 95% CI: 0.65-1.03) lower risk of GDM overall and among overweight/obese women, respectively. Interaction terms for LTPA and pre-pregnancy overweight/obesity status were not statistically significant. LTPA was not associated with risk of PIH/PE. CONCLUSION: ppLTPA was associated with decreased risk of GDM among women with normal pre-pregnancy BMI while an inverse association of epLTPA with GDM appeared to be present only among overweight/obese women. Pre-pregnancy BMI may need to be considered when recommending interventions to prevent GDM. Future studies to replicate these results are warranted.