Is There an Association Between Early Pregnancy Losses and Low 25-Hydroxy Vitamin D Levels?

Abstract

Objective: Since the etiology of pregnancy losses during first trimester has not still been clear, we aim to analyze the relationship between vitamin D deficiency and early pregnancy losses. Patients and Methods: The study was conducted on 200 women. Plasma was collected from 100 nulliparous women with singleton at 7-10 weeks of gestation (50 with viable gestation and 50 with pregnancy loss) and 100 non-gravid reproductive age women (50 with a successful pregnancy history and 50 with one or more spontaneous first trimester pregnancy loss history). Serum 25 (OH) D and calcium levels were compared between groups. Results: The serum 25(OH) D levels for the groups turned out to be 47.64 ± 3.2 (95% CI: 44.4-50.8 ng/ml) for normal pregnancy group, 27.3 ± 1.2 (95% CI: 26.1-28.5 ng/ml) for the group of early pregnancy loss, 38.5 ± 5.1 (95% CI: 33.4-43.6 ng/ml) for the non gravid women with healthy pregnancy history and 11.6 ± 4.2 (95% CI: 7.9 - 15.6 ng/ml) for the non-gravid women with history of 1 or more first trimester pregnancy loss. There was a strong correlation between low 25(OH) D levels and early pregnancy loss (odds ratio (OR): 1.70, 95% CI: 1.2-2.3, p <0.001). The calcium levels were significantly lower in pregnancy loss group than normal pregnancy and non-gravid groups (p=0.005, p=0.033 respectively). Conclusions: Although our study is emphasized on role of vitamin D in early pregnancy it is not possible to recommend screening and supplementation of vitamin D in early pregnancy, as prognosis of pregnancies receiving supplementation and the incidence of pregnancy related complications in follow-up are not known. Well designed studies with long term follow up results needed. Keywords: 25 hydroxy vitamin D, Pregnancy loss, 25 (OH) D vitamin