The coexistence of Hashimoto disease in pregnancy possesses important risk factors both for the mother and the fetus and newborn infant. The clinical and endocrinological pictures of the disease in pregnant women and their offsprings can vary greatly, and mainly depend on the type and the amount of the antithyroid auto-antibodies which cross the placenta. Transplacental passage of the anti-thyroid auto-antibodies usually leads to transient neonatal hypothyroidism. In this study we aimed to retrospectively investigate the endocrinological status of the newborn infants with maternal Hashimoto disease in the early neonatal period who were followed in our Neonatology Unit over the last 10 years. A total of 12 newborn infants were found to have maternal Hashimoto disease. Five (41.7%) of the mothers were hypothyroid and three (25%) were hyperthyroid at the time of initial diagnosis but all were euthyroid during pregnancy. None of the newborn infants had abnormal thyroid function tests or physical examination findings. Newborn infants with maternal Hashimoto disease should be followed closely for the development of thyroid function disorders in the neonatal period.

Keywords: Hashimoto hastalığı, gebelik, yenidoğan, Hashimoto disease, pregnancy, newborn