Sex-specific associations between feto-placental growth and maternal physical activity volume and sitting time: Findings from the Queensland Family Cohort study

Abstract

Introduction

Antenatal physical activity (PA) is associated with beneficial changes in placental growth and function; however, the effect of excessive sitting time is less clear. The aim of this study was to investigate whether feto-placental growth changes with maternal activity, and whether these associations differ in a sex-specific manner.

Methods

This study included women enrolled in the Queensland Family Cohort study who self-reported PA and sitting time at 24 or 36 weeks of gestation. Placental growth factors and feto-placental growth parameters at delivery were analysed by PA volume and sitting time, as well as by fetal sex.

Results

Women who reported excessive sitting time during mid-pregnancy and had a female fetus showed higher placental PlGF (p = 0.031) and FLT1 (p = 0.032) mRNA expression with no difference in placental size at delivery. For the male, excessive sitting time during mid-pregnancy was associated with a lower placental weight (p = 0.001) and placental surface area (p = 0.012) and a higher birthweight to placental weight (BWPW) ratio (p = 0.042), with no change in placental growth factors. Moderate volume PA during mid-pregnancy was associated with lower VEGFA mRNA expression in the male placenta (p = 0.005) and a higher abdominal circumference in the female neonate (p = 0.042), with no overall difference in placental weight or birthweight for either sex.

Conclusions

The results of this study suggest that mid-pregnancy may be an important timepoint for programming of feto-placental growth in relation to maternal activity. Our findings highlight the independent benefits of reducing sitting time during pregnancy, particularly for women carrying male fetuses.