Screening for thyroid dysfunction during pregnancy

Abstract

Introduction: Thyroid disorders are among the common endocrine disorders in pregnant women. It is now well established that not only overt but subclinical thyroid dysfunction can also have adverse effects on fetal and maternal outcome. Maternal hypothyroidism during pregnancy raises serious concern about long-lasting psycho-neurologic consequences for the progeny, due to the risk of insuf-ficient placental transfer of maternal thyroid hormones to the developing fetus during the first half of gestation. To validate the need of antenatal screening for maternal thyroid dysfunction this study was undertaken to know the prevalence of thyroid dysfunction among pregnant women in Central India. Materials and Methods: In this ongoing study so far 73 patients in the first trimester of pregnancy have been recruited from Matru Seva Sangh Hospital. Detailed history and examination were done. Serum thyroid-stimulating hormone (TSH) estimation was done by the immunoradiometric assay method. Results: Out of 73 patients, 30 (41%) had TSH less than 2 mIU/ml, 35 out of 73 (47.95%) had TSH between 2 mIU/ml and 4 mIU/ml. The TSH value of more than or equal to 4 mIU/ml was seen in 8/73 (10.96%). Two patients also had gestational diabetes. TSH levels were more than 2 in both. Conclusions: Prevalence of hypothyroidism is more than 10%. As per recommendations all patients with TSH levels more than 2 should be evaluated for free T4 and thyroid antibody estimation. Screening for thyroid dysfunction should be done early in pregnancy. Looking at the high percentage of abnormal TSH in pregnancies, universal screening should be considered.