The prevalence of 25-hydroxyvitamin D (25OHD) deficiency in pregnancy is high and may be associated with adverse pregnancy outcomes such as preeclampsia.

In this nested, case-controlled, longitudinal study, Agudelo-Zapata et al. assessed serum concentrations of 25OHD in 29 non-pregnant women, 61 healthy pregnant women and 20 pre-eclamptic pregnant women. 25OHD was measured across pregnancy and at 3 and 6 months post-partum, and correlated with anthropometric, biochemical and hormonal parameters. In non-pregnant women, 25OHD was measured across the menstrual cycle, and concentrations were found to be significantly lower during the follicular phase (31.9 ng/ml) compared with the luteal phase (34.9 ng/ml).

Serum concentrations of 25OHD in pregnant women were measured in the first, second and third trimesters of pregnancy and increased as pregnancy progressed. Interestingly, 25OHD concentrations were lower in the first trimester than in samples from non-pregnant women. Postpartum, 25OHD concentrations were significantly decreased compared with non-pregnant levels after both 3 and 6 months. However, no statistically significant differences in serum 25OHD concentrations were found between pre-eclamptic pregnant women and healthy pregnant women.

These results shed light on potential cross-talk between oestrogens and progesterone, which vary across the menstrual cycle and in pregnancy, and 25OHD concentrations.

Read the full article in Endocrine Connections 7 698–707