Moderate-to-vigorous intensity physicaL activity in earLy pregnancy reduces risk of gestationaL diabetes meLLitus / 中华围产医学杂志

ABSTRACT

Objective To investigate the effects of moderate-to-vigorous intensity physical activity (MVPA) in early pregnancy on the onset of gestational diabetes mellitus (GDM) in Sichuan Province. Methods A case-control study was performed on 1 508 gravidas at 8-14 gestational weeks in Sichuan Provincial Hospital for Women and Children from February to July, 2017. Baseline information during early pregnancy was collected through questionnaires. Information on time and intensity of physical activity were collected through pregnancy physical activity questionnaire. The time spent in MVPA was calculated and was categorized as active ( ≥ 3.5 h/week) or inactive MVPA (<3.5 h/week). Based on self-reported pre-pregnancy weights collected by questionnaire as well as the measured heights, body mass index (BMI) before pregnancy was calculated. After a 75 g oral glucose tolerance test (OGTT) at 24-28 gestational weeks, all subjects were divided into GDM (n=561) or non-GDM group (n=947), according to the GDM diagnostic criteria of the Guidelines for the Diagnosis and Treatment of Pregnancy Diabetes in China (2014). Mann-Whitney U test and Chi-square test were used for statistical analysis. Multivariate unconditional logistic regression model was used to analyze the association between the time of MVPA in early pregnancy and GDM incidence. ResuLts The median time spent in MVPA [M(P25-P75)] in early pregnancy was 3.00 (0.50-3.12) h/week, and 345 gravidas (22.9%) were classified as active in MVPA. After the control of confounding factors such as age, gravidity and parity history, and pre-pregnancy BMI, the multivariate unconditional logistic regression analysis showed that compared with the inactive group, the risk of GDM of active MVPA gravidas was reduced by 26.1% (OR=0.739, 95%CI 0.553-0.989, P=0.042). Among primigravidas and primiparae, the risk of GDM in active MVPA gravidas was decreased by 47.6% and 44.3% than the inactive ones, respectively (primigravidas OR=0.524, 95%CI 0.297-0.925, P=0.026; primiparae OR=0.557, 95%CI 0.357-0.868, P=0.010). ConcLusions Insufficient physical activity in early pregnancy is common in gravidas in Sichuan, China. The risk of GDM could be reduced if the frequency of MVPA during early pregnancy is no less than 3.5 h/week, especially in primigravidas and primiparae.