Outcomes of hepatitis B and hepatitis delta infection in hospitalized pregnant women in the United States: a nationwide study, 1998–2022

Hepatitis delta (HDV) is a severe viral hepatitis disease that occurs only in individuals with hepatitis B (HBV). In the pregnant population, HDV has been scarcely studied, and no guidance exists for its management. We aim to describe and compare a cohort of pregnant women with concurrent HBV/HDV infection to a cohort of pregnant women with only HBV. Utilizing the National Inpatient Sample, a database of hospitalizations throughout the United States, we extracted data from 1998 to 2022 on pregnant women with HBV and HDV using ICD-9 and ICD-10 codes. Demographics and clinical data including co-infection, comorbid condition, pregnancy complications, fetal outcomes, and mortality were collected. Analysis was performed using chi-square and logistic regression. We identified 390 pregnancies with HDV and 127,332 with HBV only. In the HDV cohort, median age was 30 years, and the predominant ethnicity/race was Asian or Pacific Islander at 27.4%. There were no cases of maternal deaths in the HDV group. Rates of hepatitis C (12.1% vs. 4.1%; p < 0.001) and cirrhosis (1.3% vs. 0.2%; p = 0.024) were significantly higher in the HDV cohort. Rates of diabetes, obesity, HIV infection, intravenous drug use, coagulopathy, and thrombocytopenia were similar between the two groups ( p > 0.05). Of those with HDV, 318 (81.5%) had known delivery. Rates of stillbirth were significantly higher in the HDV cohort (2.8% vs. 0.7%; p = 0.030). Rates of preterm and post-term birth were similar ( p > 0.05). HDV remains uncommon in pregnancy but is likely under-recognized. Pregnancies affected by concurrent HBV/HDV infection may carry a higher risk of adverse fetal outcomes, particularly stillbirth, compared to HBV alone. Not applicable.