The Effects of Vitamin D Supplementation on glycemic indices, lipid profile and blood pressure of pregnant women with Vitamin D deficiency: A Single arm Clinical Trial

Introduction: Vitamin D Deficiency (VDD) is a global problem among pregnant women in many populations. There is an association between VDD and some pregnancy outcomes, as well as gestational diabetes mellitus (GDM) and pre-eclampsia. We aimed to evaluate the effect of vitamin D supplementation on metabolic status (Fasting Blood Sugar (FBS), insulin, Homeostasis model of assessment-insulin resistance (HOMA-IR) and lipid profile) and blood pressure (BP) among pregnant women with VDD. Methods: A clinical trial was carried out on 30 pregnant women with VDD referring to the Gynecology & Obstetrics Clinic of Baqiyatallah Hospital, Tehran, Iran. The present study had two phases of vitamin D3 supplementation (50000 IU / week for 12 weeks and then 50000 IU / month for three months). Serum total cholesterol, triglyceride, Low Density Lipoprotein (LDL), High Density Lipoprotein (HDL), 25-hydroxyvitamin D (25(OH) D) level, insulin, Fasting Blood Sugar (FBS) and both systolic and diastolic blood pressure were measured. Homeostasis model of assessment-insulin resistance (HOMA-IR) was also determined. Results: The results showed that mean levels of Insulin (F=6, p=0.010), HOMA-IR (F=4.6, p=0.020), 25-hydroxyvitamin D level (F=179, p=0.001), cholesterol (F=69.7, p=0.001), triglyceride (F=69.9, p=0.001) and LDL (F=29.9, p=0.001) significantly increases during study period. However, Diastolic and systolic blood pressure, FBS, and HDL levels did not change significantly over time. Conclusion: The results of this investigation showed that weekly and monthly vitamin D3 supplementation in pregnant women with VDD had beneficial effects on glycemic status, lipid profile and blood pressure. Trial registration: The protocol of the present study has been registered in IRCT (Registration number: IRCT2014091619162N5, Registration date: 2015-03-26, https://en.irct.ir/trial/17219).