Background: Pregnancy is associated with major changes in the physiology of the thyroid gland. Undiagnosed thyroid disorders can adversely affect fetal and maternal outcome. This study was done to study the prevalence of thyroid disorder among antenatal women.Methods: This was a prospective study done in the antenatal clinic in the Department of Obstetrics and Gynaecology, ESI PGIMSRMGM Hospital, Parel, Mumbai, India.Results: In present study, fifty out of three hundred and fifty pregnant women screened had thyroid disorder. The prevalence of thyroid disorder in this study was 14.2%. The prevalence of subclinical hypothyroidism was 7.7% (n= 27), overt hypothyroidism was 4% (n=14), subclinical hyperthyroidism was 1.7% (n=6) and overt hyperthyroidism was 0.8% (n=3).Conclusions: Thyroid disorders in pregnancy are associated with adverse fetomaternal outcome. Its prevalence is high in Indian women. Thus thyroid screening should be included in the routine antenatal investigations
