(538) The Association Between Hepatitis B Virus Infection During Pregnancy and Risk of Primary Cesarean Delivery

To investigate the association between hepatitis B virus (HBV) status and the likelihood of primary cesarean section (C-section) delivery compared to vaginal delivery. 

Study Design:

This retrospective cohort study used data from the National Center for Health Statistics Vital Statistics database. The cohort linked birth and infant death data files from 2015 to 2021 was used for this study. The study included all births in the United States during the study period, with known HBV status and without prior Cesarean Delivery (CD). The outcome of interest was mode of delivery. Univariate analysis was performed to determine the association between HBV and CD rate. Multivariate logistic regression was then performed to estimate the effect of HBV status on CD adjusting for potential confounding variables. Interaction analysis was then performed to determine if the effect of HBV on CD is modified by race and obesity.

Results:

The rate of CD was higher in pregnancies complicated by HBV infection compared to uninfected individuals (22.4% vs 21.9%, p = 0.004).The effect of HBV on CD is modified by both race and obesity. Specifically, HBV infection increases risk of primary CD (aOR 1.39; 95% CI [1.25-1.54]). Compared to White, both Black and Asian race demonstrated a protective effect on primary CS among individuals with HBV infection (aOR 0.93; 95% CI [0.87 - 0.99] and (aOR 0.74; 95% CI [0.85-0.79]). Compared to underweight group, individuals in the higher weight groups complicated by HBV infection also demonstrated a protective effect on primary CD.

Conclusion:

This study demonstrated that HBV infection increased the risk of primary CD in otherwise uncomplicated pregnancies. However, in pregnancies complicated by racial categories and high BMI groups with already increased risk of primary CD, HBV infection demonstrated a protective effect.