# Association between the physical activity level in the third trimester of pregnancy and the gestational age at birth

## TL;DR

Higher sedentary activity and lower moderate exercise in late pregnancy are linked to later labor onset.

## Contribution

Identifies associations between third-trimester physical activity patterns and gestational age at birth.

## Key findings

- Women who gave birth at ≥41 weeks had higher sedentary activity and lower moderate-intensity activity.
- Cesarean delivery was associated with higher sedentary activity compared to vaginal birth.
- Reduced household/caregiving activity was observed in women delivering at ≥41 weeks.

## Abstract

The aim of this study was to evaluate the association between the physical activity level in the third trimester and the time of labor onset.

Two hundred and sixty women with low-risk pregnancies, who gave birth at 37 weeks of gestation or beyond, and completed the Pregnancy Physical Activity Questionnaire were included in this prospective, cross-sectional study. According to the gestational age at delivery, the study population was divided into case (≥41 weeks) and control (37–406/7 weeks) groups. The clinical characteristics and the physical activity levels of the two groups were compared. The physical activity levels of the participants were also compared according to the delivery route.

The nulliparity rate (54.3 vs. 21.7%), the median gestational weight gain (10.5 [2–30] vs. 10 [2–25] kg), and the cesarean delivery rate (27.7 vs. 6.6%) were higher in the case group than the control group (p<0.05). While the median level of sedentary activity was higher, the median moderate-intensity activity level and the median household/caregiving activity level were lower in the case group than the control group (p<0.05). The level of sedentary activity was also higher in women who gave birth by a cesarean section than vaginally (p<0.05).

Physical activity in the third trimester was associated with the time of labor onset. Decreased moderate-intensity and household/caregiving activity levels and an increased level of sedentary activity in the last trimester of pregnancy were found in women who gave birth at ≥41 weeks of gestation. A decreased level of sedentary activity was observed in women who gave birth vaginally.