Visceral adipose tissue during pregnancy in women with overweight or obesity and offspring metabolic health.

Background: Pre-pregnancy obesity is linked to an increased risk of adverse maternal and neonatal outcomes, and an increased likelihood of offspring obesity later in life. Accumulation of visceral adipose tissue (VAT) has been reported to be more detrimental to health outcomes than generalized obesity. Therefore, we investigated the association between maternal VAT and the metabolic health of offspring at birth.

Methods: This study was a secondary analysis of a dietary randomized controlled trial. Magnetic resonance imaging was performed in gestational weeks (GW) 15, 32, and at birth in a cohort of 119 pregnant women with a pre-pregnancy body mass index ranging from 28-45 kg/m². Offspring anthropometric measurements and cord blood samples were collected at birth. Linear regression models were applied to evaluate the association between maternal VAT and offspring outcomes. Analysis of covariance was utilized to compare offspring outcomes among mothers who exhibited either an increase or a decrease in VAT volume from GW 15 to birth.

Results: Absolute maternal VAT during pregnancy was not associated with birthweight; however, women who experienced a reduction in VAT volume during pregnancy entered pregnancy with a higher VAT volume and gave birth to heavier infants by 161 grams (95% CI, 15; 307, P = 0.031) compared to those who experienced an increase in VAT during pregnancy. Maternal VAT in GW 15 and at birth was associated with increased insulin concentrations in the offspring by 0.25 pmol/L (95% CI, 0.03; 0.46, P = 0.026) and 0.23 pmol/L (95% CI, 0.02; 0.44, P = 0.035), respectively, per 1 cm³ increase in VAT.

Conclusion: Maternal VAT, and particularly its change during pregnancy, may influence the fetal metabolic environment, impacting insulin availability and potentially fetal growth in healthy women with overweight or obesity.