Associations of Maternal Leptin with Neonatal Adiposity Differ according to Pregravid Weight

During pregnancy, maternal circulating leptin is released by maternal adipose tissue and the placenta, and may have a role in fetal development.

We investigated maternal leptinemia and glycemia associations with neonatal adiposity, taking into account pregravid weight status.

We included 235 pregnant women from the Genetics of Glucose Regulation in Gestation and Growth prospective cohort with data: blood samples collected during the 2nd trimester, an oral glucose tolerance test (OGTT), and the measured leptin and glucose levels. As an integrated measure of maternal leptin exposure, we calculated the area under the curve for maternal leptin at the OGTT (AUCleptin). Within 72 h of delivery, we measured the triceps, biceps, subscapular, and suprailiac skinfold thicknesses (SFTs); the sum of these SFTs represented neonatal adiposity. We conducted a regression analysis to assess the maternal metabolic determinants of neonatal adiposity, adjusting for parity, smoking status, maternal triglyceride levels, gestational weight gain, placental weight, delivery mode, neonate sex, and gestational age at delivery.

The pregravid BMI of the participating women was 23.3 (21.2-27.0). In the 2nd trimester, maternal AUCleptin was 1,292.0 (767.0-2,222.5) (ng × min)/mL, and fasting glucose levels were 4.2 ± 0.4 mmol/L. At delivery, the neonatal sum of 4 SFTs was 17.9 ± 3.3 mm. Higher maternal leptinemia was associated with higher neonatal adiposity (β = 4.23 mm [SE = 1.77] per log-AUCleptin; p = 0.02) in mothers with a BMI ≥25, independently of confounders and maternal glycemia, but not in mothers with a BMI <25. Higher maternal fasting glucose was associated with higher neonatal adiposity (β = 0.88 mm [SE = 0.30] per SD glucose; p = 0.005) in mothers with a BMI <25, independently of confounders and maternal leptinemia.

Maternal leptinemia may be associated with neonatal adiposity in offspring from overweight/obese mothers, independently of maternal glycemia.