Aims and Objectives To study the maternal and fetal outcome in known cases of hypothyroidism in pregnancy on treatment. Method Randomised study of 100 known cases of hypothyroidism with pregnancy on treatment admitted in Basaveshwar teaching and general hospital, attached to Mahadevappa Rampure Medical College, Kalaburgi. Conclusion-In our study it has been shown that hypothyroidism with pregnancy who were on treatment has reached up to the term without any fetal and maternal complications.