Management guidelines about the thyroid disease in pregnancy are silent about the postpartum course of new onset subclinical hypothyroidism (SCH). Hence, we analyzed the 2 years outcome of SCH diagnosed during pregnancy.
We conducted this retrospective study using the medical records of patients with new onset SCH during pregnancy between 2010 and 2013 ( n = 718). Patients who stopped their levothyroxine after delivery with a 2-year follow-up record were included. We excluded patients with known thyroid disorders and continuous use of drugs that affect the thyroid results. The patients were divided into two groups (Group 1 – euthyroid and Group 2 – hypothyroid) based on the final outcome after 2 years. The data were analyzed using appropriate statistical methods and a P < 0.05 was considered statically significant.
A total of 559 (77.8%) women stopped levothyroxine after delivery, and the final follow-up data were available for 467 patients only. At the end of 2 years, 384 (82.2%) remained euthyroid, and the remaining 83 (17.8%) developed hypothyroidism. SCH and overt hypothyroidism were seen in 22 and 61 patients, respectively. Group 2 patients had higher mean age (25.5 vs. 23.6 years), goiter (51 vs. 2%), initial thyroid stimulating hormone (7.9 vs. 5.1 μIU/mL), and thyroid antibody positivity (76 vs. 13%) ( P < 0.001).