The effect of different doses of vitamin D supplementation on insulin resistance during pregnancy.
Low serum vitamin D levels are correlated with insulin resistance during pregnancy. We have assessed the effects of different doses of vitamin D on insulin resistance during pregnancy. A randomized clinical trial was done on 120 women with a gestational age of less than 12 weeks. The women were divided into three groups randomly. Group A received 200 IU vitamin D daily, group B 50,000 IU vitamin D monthly and group C 50,000 IU vitamin D every 2 weeks from 12 weeks of pregnancy until delivery. The serum levels of fasting blood sugar (FBS), insulin, calcium and 25-hydroxyvitamin D were measured before and after intervention. We used the homeostatic model assessment of insulin resistance (HOMA-IR) as a surrogate measure of insulin resistance. The mean ± standard deviation of serum 25-hydroxyvitamin D increased in group C from 7.3 ± 5.9 to 34.1 ± 11.5 ng/ml and in group B it increased from 7.3 ± 5.3 to 27.23 ± 10.7 ng/ml, but the level of vitamin D in group A increased from 8.3 ± 7.8 to 17.7 ± 9.3 ng/ml (p < 0.001). The mean differences of insulin and HOMA-IR before and after intervention in groups A and C were significant (p = 0.01, p = 0.02). This study has shown that supplementation of pregnant women with 50 000 IU vitamin D every 2 weeks improved insulin resistance significantly.
Department of Endocrinology, Yazd Diabetes Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. s_soheilykhah@yahoo.com
Sedigheh
S
Soheilykhah
Mahdieh
M
Mojibian
Maryam Jannati
MJ
Moghadam
Ahmad
A
Shojaoddiny-Ardekani
D000328:Adult; D001786:Blood Glucose / Q000187:drug effects*; D002118:Calcium / Q000097:blood; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D011247:Pregnancy; D014807:Vitamin D / Q000008:administration & dosage* / Q000097:blood
D001786:Blood Glucose; D007328:Insulin; D014807:Vitamin D; D002118:Calcium