Background: In developing countries, 18% of global burden of diseases has been related to pregnancy complications. Research shows significant association between Vitamin D deficiency in pregnancy and elevated risk for preeclampsia, GDM and anaemia. Regulation of Vitamin D levels and management of hypovitaminosis D is most important mainly in developing countries and low resource healthcare settings to decrease the chances of pre eclampsia and GDM and also to improve the quality of life of women. This study will also help obstetricians to consider effects of hypovitaminosis D in pregnant women and to reduce the maternal morbidity because of its complications. Aim & Objectives: To study the level of Vitamin D in antenatal women at 20 weeks, at term and in fetal cord serum and also o study the association of Vitamin D levels with pre eclampsia and GDM. Material and Methods: A hospital based study was conducted among 210 antenatal females who came at <20 weeks of gestation inMuzaffarnagar Medical College & Hospital, Muzaffarnagar, Uttar Pradesh. Study was conducted for 18 months.Data was analysed statistically and chi square test was applied. Results: There is a significant association between gravida status and both preeclampsia (p-value = 0.001) and GDM (p-value = 0.01). There is a significant association between the use of vitamin D supplements and preeclampsia (p-value = 0.05), but not with GDM (p-value = 0.11). The p-values for preeclampsia (<0.05) and GDM (<0.05) indicate significant associations between low vitamin D levels (<20 ng/ml) both at <20 weeks and at term and the occurrence of preeclampsia and GDM. Neonates from the control group show higher vitamin D levels in cord blood compared to those from preeclampsia and GDM groups, as supported by the significant p-values. Conclusion: Our findings conclude that significant association between low vitamin D levels and the occurrence of preeclampsia and GDM has been found. Primigravida women and those not using vitamin D supplements were at higher risk for these conditions. The findings highlighted the importance of monitoring and potentially supplementing vitamin D levels during pregnancy to reduce the risk of preeclampsia and GDM. Neonates from preeclamptic and GDM mothers also exhibited lower cord blood vitamin D levels.