Maternal prenatal cortisol trajectories predict accelerated growth in infancy

Area of Science:

• Reproductive biology
• Developmental psychology
• Endocrinology

Background:

• Elevated maternal cortisol during pregnancy is associated with childhood obesity.
• Previous studies measured maternal cortisol at a single time-point, limiting understanding of critical timing effects.

Purpose of the Study:

• To investigate the longitudinal impact of maternal cortisol trajectories during pregnancy on infant growth.
• To identify distinct patterns of maternal cortisol exposure throughout gestation.

Main Methods:

• Longitudinal measurement of maternal plasma cortisol at four gestational time-points (15, 19, 25, 31 weeks).
• Assessment of infant body mass index percentile (BMIP) at multiple time-points from birth to 24 months (n=189).
• Application of general growth mixture modeling (GGMM) to identify cortisol trajectories and multilevel modeling to predict child growth.

Main Results:

• Three maternal cortisol trajectories were identified: typical, steep, and flat.
• Infants of mothers with flat cortisol trajectories (high early, plateauing) showed increased BMIP from birth to 6 months.
• These infants had higher BMIPs at 3 and 6 months compared to those with typical or steep trajectories.

Conclusions:

• The timing and trajectory of prenatal maternal cortisol exposure, not just the total amount, influence early infant growth.
• Specific maternal cortisol patterns during gestation may contribute to early obesity risk.
• Further research is needed to identify factors influencing maternal prenatal cortisol trajectories.