Maternal and perinatal outcome in thyrotoxicosis complicating pregnancy

In this report we describe 32 pregnancies complicated by hyperthyroidism cared for over a 7-year period at AIIMS, New Delhi. In 6 cases hyperthyroidism was diagnosed during pregnancy; others were diagnosed before conception and were on antithyroid therapy during pregnancy. For control of thyrotoxicosis thiourea derivatives, carbimazole (CMZ) and propylthiouracil (PTU), were both used. The dosage of antithyroid drugs could be decreased or stopped in the third trimester in only 28% cases, while 50% cases did not require any change in the dosage during gestation and 21% required an increase in dosage with advancing gestation to control thyrotoxicosis. Maternal and fetal complications included preterm labour (25%), PIH (22%), thyroid crisis (9%) and intrauterine growth retardation (13%). Thyroid status of neonates was found abnormal in 9% cases, including 1 case (3%) of neonatal thyrotoxicosis with goitre and 2 (6%) cases of neonatal hypothyroidism. One maternal death occurred due to thyroid storm. No case of stillbirth or perinatal death occurred in the present study. In our experience of 32 cases maternal and fetal complications are reported with increased frequency, requiring close surveillance of thyroid status to maintain euthyroidism and intensive fetal monitoring during pregnancy to achieve good maternal and perinatal outcome.