Low serum vitamin D level is associated with intrahepatic cholestasis of pregnancy.

Abstract

Intrahepatic cholestasis of pregnancy (ICP) is a unique hepatic disorder of pregnancy and is related to adverse maternal and perinatal outcomes. The pathogenesis of the disease is not clear and appears to be multifactorial. There is increasing evidence that vitamin D (Vit D) plays a role in hepatobiliary homeostasis and in various liver diseases. We aimed to investigate the association between serum Vit D level and ICP. A total of 40 pregnant women with ICP and 40 healthy pregnant women were included in this controlled cross-sectional study. Their demographic characteristics, including age, body mass index (BMI), gestational week, gravidity and parity, and laboratory parameters, including 25(OH) Vit D3 levels, liver function tests, fasting and postprandial bile acid concentrations, were recorded. Gestational age at delivery, birth weight (BW), neonatal intensive care unit (NICU) admission, meconium staining of amniotic fluid and appearance pulse grimace activity respiration (APGAR) score at 5 min were obtained from medical records for assessment of perinatal outcomes. There was no significant difference between groups in terms of demographic characteristics. The mean serum 25(OH) Vit D3 level was significantly lower in pregnant women with ICP compared to control pregnant women (8.6 ± 4.9, 11.3 ± 6.1; P =0.033), and it was significantly lower in severe disease than mild disease (6.9 ± 2.1, 10.3 ± 6.2, respectively; P =0.029). We also found that lower serum 25(OH) Vit D3 levels were significantly and inversely correlated with fasting and postprandial bile acid levels. However, in subgroup analyses in ICP pregnant women, there was no difference in mean 25(OH) Vit D3 levels for women with or without perinatal complications. Our study suggests that low levels of 25(OH) Vit D3 were associated with ICP disease and its severity. However, further larger studies are needed to evaluate the effect of Vit D in the pathogenesis and outcome of the disease.