<prompt> In a pregnant lady with hyperthyroidism , the safest drug to be used is -PropylthiouracilMethimazoleCarbimazoleLugols Iodine  <response>: Ans. is a i.e., Propylthiouracil Propylthiouracil is the DOC for hyperthyroidism in pregnancy. Methimazole and carbimazole used in early pregnancy have been associated with esophageal and choanal atresia, aplasia cutis, and fetal agranulocytosis. Graves disease is the MC cause of hyperthyroidism in pregnancy. Hashimotos thyroiditis is the MC cause of hypothyroidism in pregnancy. Complications associated with both hypo- and hyperthyroidism in pregnancy:1 Recurrent first trimester abortions2 IUGR3 Increased risk of preeclampsia4 Abruption5 Stillbirths, hydrop fetalis6 Preterm labor Hypothyroidism is also associated with cretinism. 