Decreased maternal hypothalamic-pituitary-adrenal axis activity in very severely obese pregnancy: Associations with birthweight and gestation at delivery

Highlights • Circulating maternal cortisol levels are lower in very severely obese pregnancy than in lean pregnancy. • Other key hormones regulating pregnancy cortisol levels including CRH and CBG are lower in obese pregnancy. • A lack of increase in urinary glucocorticoid clearance suggests a lesser activation of the HPAA in obese pregnancy. • This may offer a novel mechanism underlying increased birth weight and longer gestation in obese pregnancy.