Maternal psychological distress, prenatal cortisol, and fetal weight.

Objective: The objective of this study was to examine the effects of maternal psychological distress on estimated fetal weight during midgestation and explore the maternal hypothalamic-pituitary axis and sympathoadrenal dysregulation as potential risk factors for these effects.

Methods: Fetal ultrasound biometry measurements and maternal sociodemographic characteristics, emotional distress symptoms, and first morning urine samples were collected during a clinical ultrasound examination for a cross-sectional sample of 98 women who were between 16 and 29 weeks pregnant. Fetal weight was estimated from ultrasound biometry measurements; maternal emotional distress was assessed using the daily hassles (stress), Center for Epidemiologic Studies-Depression (depression), and State-Trait Anxiety Inventory (anxiety) scales; and urine samples were assayed for cortisol and norepinephrine levels.

Results: Correlation analyses revealed that both maternal psychological (daily hassles, depression, and anxiety) and biochemical (cortisol and norepinephrine) variables were negatively related to fetal biometry measurements and estimated fetal weight. A structural equation model further revealed that when the independent variance of maternal sociodemographic, psychological distress, and biochemistry measures were accounted for, prenatal cortisol was the only significant predictor of fetal weight.

Conclusions: Women exhibiting psychological distress during pregnancy exhibit elevated cortisol levels during midgestation that are in turn related to lower fetal weight.