Feto-maternal Outcome Using New Screening Criteria of Serum TSH for Diagnosing Hypothyroidism in Pregnancy

Abstract

Introduction: Evidence suggests that by using the classical non pregnant reference range for serum TSH (STSH), one might miss hypothyroidism in pregnancy. Therefore, upper normal cut off value of S TSH should be taken as 3mIU/L, for diagnosing hypothyroidism in pregnancy. Materials and Methods: This study was a cross sectional study, carried out in the Department of Obstetrics and Gynaecology of a tertiary care hospital, in collaboration with the Department of Endocrinology. Pregnant women with ≤ 20 weeks gestation, attending antenatal OPD from December 2010 to January 2012 were included in the study. On the basis of S TSH level, women were divided into Study Group with S TSH level between 3.1 to 6.2 mIU/L, (new range to be studied) and an equal number of age and parity matched Control Group with S TSH levels between 0.4 to 3 mIU/L. The maternal and fetal outcomes were compared between study and control groups. Results: During the study period, a total of 66 women had S TSH between 3.1-6.2 mIU/L. Maternal and fetal outcomes in both the groups were comparable. There was no difference in the mode of delivery between study and control groups. Conclusion: The lower S TSH cut off recommended for diagnosing hypothyroidism in pregnancy may not be applicable to pregnant Indian women.

Keywords

• endocrinological disorders
• reference values
• screening in pregnancy
• serum tsh