Serum Bile Acid Levels in Women With Intrahepatic Cholestasis of Pregnancy in India

Abstract

Introduction: Intrahepatic cholestasis of pregnancy (ICP) manifests as unexplained intense pruritus in the third trimester of pregnancy and is often diagnosed based on elevated serum bile acid measurement. There are no data from India on serum bile acid levels in pregnant women with ICP. Methods: Pregnant women with significant pruritus during the third trimester of gestation and with elevated serum alanine aminotransferase and/or aspartate aminotransferase (normal: <40 IU/L) were taken as having ICP. Serum BA levels were measured in them and in nonpregnant women and healthy pregnant women without itching. Results: Of the 3735 pregnant women screened, 105 (2.8%) had ICP (age 28 [26-32] years; gestational age 32 [30-36] weeks; primigravida 32.3%, and 95.3% normal fetal growth). Median (interquartile range) serum bile acid levels in nonpregnant women (n = 61; 28 [25-31] years) and pregnant women without ICP (n = 59; 28 [25-31] years) were similar (3.7 [1.6-5.1] μmol/L and 3.7 [2.2-5.8] μmol/L, respectively). By comparison, serum bile acid level in women with ICP (n = 105; 28 [26-32] years) was significantly higher (20.2 [12.7-39.5] μmol/L; P < 0.05 each), being above 10 μmol/L in 88 (83.8%). The optimum cut-off for the diagnosis of ICP in our population was ≥8.6 μmol/L, with sensitivity of 87.6%, specificity of 93.3% and area under the receiver-operator characteristics curve of 0.937 (95% CI: 0.904-0.970). Conclusion: Serum BA levels in healthy Indian nonpregnant and pregnant women are similar to those in other populations and can be used to diagnose ICP with an optimal cut-off being 8.6 μmol/L.