Congenital Hypothyroidism Can Dictate the Mode of Delivery and Intra-labor Medication Usage

Pregnancy and parturition reflect the complex interaction between physiologic conditions of the mother and her offspring, and fetal health characteristics may affect maternal health throughout pregnancy and delivery. We investigated the characteristics of the mother-infant dyad of term infants detected by the National Newborn Screening Program as having congenital hypothyroidism (CH) (131 out of 108,717; 0.12%). Three years of surveillance in our Pediatric Endocrine Clinic revealed that 65 had transient CH and 66 had permanent CH. A higher proportion of deliveries of CH infants required vacuum assistance, and more infants with CH were born through a cesarean section compared to the general population (p<0.001). Medication during labor also differed, with higher rates of oxytocin (p<0.001) and antibiotics (p=0.008) administered to mothers of CH infants. A multivariate logistic regression model revealed an increased demand for oxytocin administration during the labor of a CH infant in a hypothyroidism severity-dependent manner, expressed as a threefold risk associated with permanent but not transient CH. Our findings of increased utilization of medical interventions during the labor and delivery of CH infants suggest that the prenatal fetal thyroid function affects the development and progress of labor and delivery, in response to oxytocin.