Aims The purpose of the study was to determine the prevalence of osteomalacia and hypovitaminosis D among diabetic and non-diabetic pregnant women and in their neonates. Methods Serum calcium, phosphorus, heat labile alkaline phosphatase, 25(OH) vitamin D and PTH were measured in 32 non-diabetic, 16 gestational diabetic and 8 Type 1 diabetic pregnant women and in cord blood of their newborn. Results Among 32 non-diabetic subjects, 4 subjects (12.5%) had biochemical osteomalacia. 4 out of 16 gestational diabetic subjects (25%) had biochemical osteomalacia whereas 5 out of 8 Type 1 diabetic subjects (62.5%) had biochemical osteomalacia. Mean concentration of 25(OH) vitamin D in the non-diabetic group was 17.18 ± 9.88 ng/ml. Mean concentration of 25(OH) vitamin D in the Gestational diabetic group was 14.75 ± 6.90 ng/ml, while in Type 1 diabetic group, it was 7.81 ± 3.79 ng/ml. 50% of neonates of normal pregnant women had vitamin D deficiency whereas, 50% had vitamin D insufficiency. 40% of neonates of Gestational diabetic pregnant women had vitamin D deficiency whereas, 40% had vitamin D insufficiency. Conclusion Vitamin D deficiency and biochemical osteomalacia was present in significant percentage of normal pregnant women and their neonates. Gestational diabetes and Type 1 diabetic women were more prone to develop vitamin D deficiency and biochemical osteomalacia.