In India thyroid disorders are in a transition zone from a predominant iodine deficient nation to now an iodine sufficient population. Rate of foetal loss is twice normal, there is increased risk of preterm delivery, 10 to 20% congenital anomalies and poor somatic and intellectual developments in 50 to 60% of surviving offspring, if pregnancy was complicated by thyroid disorders. This is a prospective study consists of cases of documented pregnancies recruited from department of obstetrics & gynaecology at Sri Krishna medical college and hospital, Muzaffarpur, from April 2017 to march 2018.500 antenatal women irrespective of thyroid status at first visit will be screened for hypothyroidism by TSH level. In present study, the incidence of foetal complication in women with subclinical hypothyroidism was LBW (7.04%), IUGR (4.2%), foetal distress (11.2%) and foetal death (0%).In present study, the incidence of foetal complication in women with overt (uncontrolled) hypothyroidism was LBW (20.68%), IUGR (17.24%), foetal distress (13.79%) and foetal death (0%).LBW found in 7.04% (5/71) women with subclinical hypothyroidism and 20.68% (6/29) women with overt hypothyroidism.