This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Management and Long-Term Consequences, Subject name: Gynaecology & Obstetrics
DOC for hyperthyroidism in pregnancy: 
Select and explain. 
A. Propylthiouracil, B. Methimazole, C. I-131, D. Thyroxine
A: Propylthiouracil
Answer: A: Propylthiouracil 
Explanation: Ans. (a) PropylthiouracilRef DC Dutta 7th ed./ 287; Harrison's 19th ed./ 2297* For the hyperthyroidism during pregnancy the mainstay of treatment in 1st trimester is PTU or methimazole.* Methimazole is preferable avoided during first trimester of pregnancy if PTU is available.* Methimazole and carbimazole is avoided due to fetal aplasia cutis and other defects such as choanal atresia.* Because of its rare association with hepatotoxicity, propylthiouracil should be limited to the first trimester and then maternal therapy should be converted to methimazole (or carbimazole).