Endocrine Abstracts

Introduction: In pregnant women there is a twofold increase in synthesis of calcitriol, i.e. the active metabolite of vitamin D. Literature data point to adverse effects of vitamin D deficiency during pregnancy both for pregnant woman and foetus. Polish data on the effects of vitamin D deficiency in this group are scarce.

Aim of the study: The aim of this study was to evaluate the relationship between vitamin D3 concentrations in pregnant women on health of pregnant women and newborns.

Patients and methods: The study included 109 healthy pregnant women, aged 21–40 years, (30.5±4.9 years). 60 of women completed a questionnaire on the course of pregnancy, childbirth and child health. Women were divided into three groups: those with sufficient serum vitamin D3 – above 30 ng/ml, with vitamin D3 insufficiency – 25(OH)D concentrations in the range of 20–30 ng/ml and vitamin D deficiency (<20 ng/ml).

Results: Insufficient concentrations of vitamin D deficiency are common in Polish pregnant women. Optimal vitamin D concentrations were found only in 16% of women in winter and in 47% in summer (P<0.03). Bacterial vaginosis was significantly more common in the group of women with vitamin D deficiency (P<0.005), whereas there was no effect of vitamin D level on the incidence of gestational diabetes, pre-eclampsia and the method of labour. There was no relation between concentrations of vitamin D during pregnancy and parameters determining size of a newborn. There was an increased incidence of respiratory tract infections in children whose mothers had been vitamin D deficient.

Conclusions: i) Vitamin D deficiency in pregnancy is common and particularly severe in winter months. ii) Vitamin D deficiency in pregnant women contributes to development of bacterial vaginosis, and increased frequency of respiratory infections in a child, thus confirming the role of vitamin D in prevention of infections.