Decreased Physical Activity during Pregnancy Is Associated with Excessive Gestational Weight Gain

The majority of pregnant women in Taiwan are not considered physically active. During pregnancy, many women decrease their physical activity levels when compared to pre-pregnancy. The purpose of this study was to examine the association between decreased physical activity from pre-pregnancy to pregnancy and excessive gestational weight gain (GWG). This study applied a prospective panel design. Recruitment was conducted at six medical facilities in Taiwan and lasted from August 2016 to April 2017. Physical activity levels were determined both before and during pregnancy using the International Physical Activity Questionnaire—Short Form, with data subsequently being transformed into METs-min/week. Excessive GWG was determined based on the body mass index (BMI) specific GWG range. We recruited 747 pregnant women in their second trimester and followed them through to one-month postpartum. About 40% of participants (41.2%) exhibited excessive GWG. Physical activity decreased from an average of 2261 (SD = 3999) to 1252 (SD = 2258) METs-min/week from pre-pregnancy to pregnancy (p < 0.0001). Controlling for age and pre-pregnancy BMI, a logistic regression model revealed that a decline in physical activity of > 4000 METs-min/week from pre-pregnancy to pregnancy was associated with an increased risk for excessive GWG (OR = 2.83, 95% CI: 1.27–4.43). A substantial decrease in physical activity from pre-pregnancy to pregnancy was a risk factor for excessive GWG. Although most women decreased their physical activity during pregnancy, only those pregnant women who were physically active pre-pregnancy could show the kind of large decrease that resulted in excessive GWG. Health professionals should continue to develop strategies for counteracting the problematic trend of decreasing PA during pregnancy among low-risk pregnant women.