The Epidemiology of Liver Diseases Unique to Pregnancy in a US Community: A Population-Based Study

Background & Aims: Little is known in the United States about the epidemiology of liver diseases that develop only during (are unique to) pregnancy. We investigated the incidence of liver diseases unique to pregnancy in Olmsted County, Minnesota, and long-term maternal and fetal outcomes. Methods: We identified 247 women with liver diseases unique to pregnancy from 1996 through 2010 using the Rochester Epidemiology Project database. The crude incidence rate was calculated by the number of liver disease cases divided by 35,101 pregnancies. Results: Of pregnant women with liver diseases, 134 had preeclampsia with liver dysfunction, 72 had hemolysis-associated increased levels of liver enzymes and low-platelet (HELLP) syndrome, 26 had intrahepatic cholestasis of pregnancy, 14 had hyperemesis gravidarum with abnormal liver enzymes, and 1 had acute fatty liver of pregnancy. The crude incidence of liver diseases unique to pregnancy was 0.77%. Outcomes were worse among women with HELLP or preeclampsia than the other disorders-of women with HELLP, 70% had a premature delivery, 4% had abruptio placentae, 3% had acute kidney injury, and 3% had infant death. Of women with preeclampsia, 56.0% had a premature delivery, 4% had abruptio placentae, 3% had acute kidney injury, and 0.7% had infant death. After 7 median years of follow-up (range, 0-18 years), 14% of the women developed recurrent liver disease unique to pregnancy; the proportions were highest in women with initial hyperemesis gravidarum (36%) or intrahepatic cholestasis of pregnancy (35%). Women with preeclampsia were more likely to develop subsequent hepatobiliary diseases. Conclusions: We found the incidence of liver disease unique to pregnancy in Olmsted County, Minnesota, to be lower than that reported from Europe or US tertiary referral centers. Maternal and fetal outcomes in Olmsted County were better than those reported from other studies, but fetal mortality was still high (0.7%-3.0%). Women with preeclampsia or HELLP are at higher risk for peripartum complications and subsequent development of comorbidities.