Background <p>Vitamin D (Vit-D) deficiency is considered a path to metabolic disturbance during pregnancy, especially among women with gestational diabetes mellitus (GDM). This study aimed to investigate the impact of Vit-D status on hyperlipidemia, hyperuricemia, and hypocalcemia in pregnant women with GDM in Bangladesh.</p> Materials and methods <p>Serum biochemical parameters were measured in 335 pregnant women using an automated chemistry and immunoassay analyzer. The associations among these parameters were investigated using the IBM SPSS statistical package. A P value of less than 0.05 was considered statistically significant.</p> Results <p>Among the population, 80.30% and 19.70% were without GDM and GDM, respectively. 30.45%, 48.36%, and 21.19% of the participants were identified as Vit-D sufficient (&gt; 30 ng/mL), insufficient (20–30 ng/mL), and, deficient (&lt; 20 ng/mL) respectively, with a higher prevalence of Vit-D deficiency and insufficiency in the second trimester during pregnancy. Serum Vit-D levels were significantly positively associated with calcium and HDL levels, whereas negative associations were observed with uric acid, fasting blood sugar (FBS), cholesterol (Cho), triglycerides (TG), and LDL (<i>p</i> &lt; 0.05). Remarkably, significantly (<i>P</i> &lt; 0.01) increased levels of uric acid, Cho, TG, LDL, and FBS along with decreased Ca and HDL were observed in the Vit-D-deficient plus GDM group, compared to Vit-D-sufficient plus without GDM group.</p> Conclusion <p>Pregnant women with GDM, particularly those with Vit-D deficiency, are significantly associated with a high risk of hyperlipidemia, hyperuricemia, and hypocalcemia. The outcomes of this study emphasize the importance of routine Vit-D screening during pregnancy to minimize the threat of hostile metabolic outcomes during pregnancy and the postpartum period.</p> Clinical trial number <p>Not applicable.</p>