Objectives: This randomized controlled trial was conducted to evaluate efficacy and safety of glyburide (glibenclamide as available in India) compared to insulin for treatment of hyperglycaemia in pregnancy (HIP) including gestational diabetes mellitus and type-2 DM, with offspring follow up to 7-10 years for long-term consequences. Materials and Methods: Total 80 cases of GDM diagnosed on OGTT (100 gm) by Carpenter-Coustan cut-offs and remained uncontrolled on MNT type-2 DM, between 12 to 34 weeks gestation, were enrolled after taking informed consent and randomized into two groups. Group-I (n=40) received oral glibenclamide and group-II (n=40) received Insulin. Glibenclamide therapy was considered failed if targets BS could not be achieved with maximum glibenclamide dose (20 mg) and patient was switched over to insulin.Primary outcome measures wereglycemic control and time taken for achieving normoglycemia and failure of therapy. Secondary outcomes were dose requirement, maternal hypoglycemia, fetal complications- macrosomia, intrauterine death (IUD), congenital malformations, neonatal hypoglycemia and neonatal intensive care unit (NICU) admission and long-term follow up of children born. Results: Baseline profile of patients in both groups was comparable. In group I, 31 subjects required twice daily doses. Mean ±SD (range) of daily glibenclamide dose was 5.5±3.6 (2.5-17.5) mg. Mean glibenclamide dose was 3.75 for morning single dose, 3.55 mgfor evening single dose and 2.7 mgeach in patients requiring twice daily dose.In group-II the mean insulin required was 28.8 ± 9.6 (8-45) units in 4 divided dosages of approximately 6-7 units. There was no difference in the time taken to attain glycemic control in the two groups which was 17 days and 15.5 days in group I and II respectively (p=0.57). At recruitment the mean HbA1c (in %) was 6.2±0.28 and 6.4±0.43(p=0.22) which reduced to 5.3±0.53 and 5.8±0.(p=0.01) at delivery in group I and group II respectively indicating better control of HbA1c levels with glibenclamide. None of the babies in group-I including two cases of type 2DM who continued glibenclamide in first trimesterhad any congenital malformation. In group II, two babies had congenital malformations: BS-F was more significantly correlated to the control on nutrition alone vs treatment requirement. All patients with BS-F<95 mg/dL achieved normoglycemia on MNT and did not require pharmacologic treatment. Patients with BS-F >110 mg/dLcould not be controlled on diet alone throughout pregnacy. Fasting value <135 could not be controlled on diet initially also in GDM cases. Nutan GDM grading is proposed on basis of fasting blood sugar lavels. Two cases (5%) had failure of therapy with glibenclamide and switched over to insulin therapy both had hypothyroidism. In group I, hypoglycemic attacks were seen in 4(10%) cases. In insulin group,  hypoglycemia was seen in 3 (7.5%) cases. There were two IUD in group I, both had preeclampsia. One neonatal death occurred in group 2. Neonatal outcome was comparable in both groups. Offsprings of glibenclamide group showed no adverse consequences at 7-10 year follow up Conclusions: Glibenclamide is comparable to insulin in treating diabetes in pregnancy with similar obstetrical, maternal or perinatal outcomes andis not associated with any long term adverseconsequences in the offspring.