An observational study to determine the association of thyroid hormones with pre-eclampsia

Objectives: Identifying pregnancies that are at an increased risk of pre-eclampsia is challenging. The present study was done to determine the role of maternal thyroid function for predicting the development of pre-eclampsia. Methods: This prospective observational cohort study was conducted for 18 months on 200 patients. The patients were tested for thyroid-stimulating hormone (TSH, mIU/L), anti-thyroid peroxidase (anti-TPO, IU/mL) antibodies and free thyroxine (FT4, ng/dL) at 11–18 weeks of pregnancy. After 20 weeks, the development of pre-eclampsia was assessed. Results: Amongst 200 patients, 38 (19%) developed pre-eclampsia. Patients with pre-eclampsia had significantly higher TSH (7.15 vs. 2.54 mIU/L, P < 0.0001), significantly lower FT4 (0.93 vs. 1.12 ng/dL, P < 0.0001) and significantly higher anti-TPO (42.38 vs. 19.78 IU/mL, P = 0.001). TSH was the best predictor of pre-eclampsia at >5.68 mIU/L with 75% diagnostic accuracy. Conclusion: Thyroid profile derangement has a significant association with pre-eclampsia, and it can predict pre-eclampsia in early pregnancy with TSH levels being the best predictor.