Maternal early pregnancy serum level of 25‐Hydroxyvitamin D and risk of gestational diabetes mellitus

Objective To assess if early pregnancy (≤14 weeks of gestation) 25‐hydroxyvitamin D (25(OH)D) level is associated with risk of gestational diabetes mellitus (GDM). Methods A nested case‐control study (60 women in each arm) was conducted at Saad Abualila Hospital (Khartoum, Sudan) during the period of January to November 2017. Clinical and obstetrical data were gathered, 25(OH)D concentration was measured at the first prenatal visit, and a 75‐g oral glucose tolerance test was performed at 24–28 weeks of gestation. Results Compared with women without GDM, in women with GDM, the median of the 25(OH)D level was significantly lower (7.3 [interquartile range 5.7–8.8] ng/mL versus 8.4 [interquartile range 6.6–11.9] ng/mL, P=0.001). All women in the study (with and without GDM) had vitamin D deficiency (25(OH)D