Maternal exposure to analgesics in late pregnancy was associated with fetal ductal constriction compared with unexposed controls. The association was stronger for metamizole and consistent with a dose-related pattern. Acetaminophen was associated with mild, reversible ductal involvement in a subset of fetuses. Reversibility after drug withdrawal supports a functional, prostaglandin-mediated mechanism. These findings have important implications for maternal analgesic use in late gestation and highlight the value of Doppler surveillance following exposure to prostaglandin-modulating agents.
Rocha et al. (Sun,) studied this question.