title: Vitamin D status and gestational diabetes mellitus.
abstract: BACKGROUND
  Vitamin D (Vit D) deficiency and gestational diabetes mellitus (GDM) are increasingly being seen in Indian women. The role of Vit D in causing GDM is not clear.
  
  
  OBJECTIVE
  (1) To compare Vit D status in pregnant women with or without GDM. (2) Frequency of GDM in women with Vit D insufficiency and deficiency. (3) To reassess glucose tolerance after replacement of Vit D in those women with Vit D deficiency and GDM.
  
  
  METHODS
  Tertiary Care Hospital, Antenatal Care Department based prospective, controlled study.
  
  
  METHODS
  Seventy-eight consecutive women (<28 weeks gestational period) were screened for GDM by glucose tolerance test (GTT) (75 g 2 h). Fifty-nine of these women were confirmed to have GDM (2 h postglucose > 140 mg/dl). Eight of these women were excluded as per laid exclusion criteria. Remaining 19 women with normal glucose tolerance (NGT) were included as controls. Serum 25-OH Vit D level was estimated by radioimmuno assay. Standard advice regarding diet, sunlight exposure, and exercise was given to all by the same dietician. Women with Vit D levels below 20 ng/ml were prescribed 60,000 IU of oral cholecalciferol to be administered twice weekly for 4 weeks. GTT was repeated after 6 weeks. Frequency of glucose intolerance was compared between Vit D sufficient and deficient groups. Women with GDM and Vit D deficiency who revert to NGT after supplementation with cholecalciferol were evaluated.
  
  
  METHODS
  Paired t-test for comparing means, and Fisher's test for comparing proportions.
  
  
  RESULTS
  Baseline characteristics of GDM and NGT with respect to their age, prepregnancy body mass index, and gestational period were comparable. Serum 25-OH Vit D levels were significantly lower in GDM 24.7 (±17.6) ng/ml versus NGT (45.8 ± 28) group (P = 0.0004). Frequency of GDM was similar irrespective of Vit D status 67% versus 42% (P = 0.09). Standard advice on diet and exercise with or without Vit D supplementation did not significantly differ in the conversion of GDM to NGT (P = 0.63).
  
  
  CONCLUSIONS
  Although Vit D deficiency is associated with GDM however its replacement does not reverse the glucose intolerance. There is no justification at present for routine screening for Vit D deficiency or its replacement in the management of GDM.
authors.affiliation: Department of Endocrinology, Command Hospital (SC), Wanowrie, Pune, Maharashtra, India.
authors.forename: Jayaraman
authors.initials: J
authors.lastname: Muthukrishnan
authors.affiliation: Department of Medicine, Armed Forces Medical College, Pune, Maharashtra, India.
authors.forename: Goel
authors.initials: G
authors.lastname: Dhruv
keywords: Gestational diabetes mellitus; Vitamin D; glucose intolerance