Multiple congenital anomalies in a late-preterm neonate: A case of possible carbimazole embryopathy

The use of carbimazole in the treatment of hyperthyroidism in pregnant women is associated with several congenital anomalies, especially when used during early pregnancy. Some of the reported congenital anomalies include aplasia cutis congenita, choana/esophageal atresia, facial dysmorphism, and cardiovascular/gastrointestinal anomalies. We report the case of a 17-day-old late-preterm neonate who presented with complaints of difficulty in breathing, darkening of the lips/extremities, and abnormal facies observed since birth. The mother had been on tablet carbimazole 20 mg daily for the treatment of hyperthyroidism until the fifth week of gestation from the time she was confirmed to be pregnant. Physical examination and further evaluations revealed multiple congenital anomalies, including facial dysmorphism, bilateral arthrogryposis of the lower limbs, micropenis, complex congenital heart disease, and intestinal obstruction. This case report, therefore, highlights the need to avoid the use of imidazole derivatives such as carbimazole during the pre-conception period as well as in the first trimester of pregnancy.