Update on viral hepatitis in pregnancy
ABSTRACT
Pregnant women with acute viral hepatitis are at higher risk of morbidity and death than pregnant women with chronic viral hepatitis. The risk of death is highest with acute viral hepatitis E, and the rate of transmission to the baby may be highest with hepatitis B virus (HBV) infection. Managing viral hepatitis in pregnancy requires assessing the risk of transmission to the baby, determining the gestational age at the time of infection and the mother’s risk of decompensation, and understanding the side effects of antiviral drugs.
KEY POINTS
- Preventing vertical transmission of HBV infection in pregnancy is key to decreasing the global burden of this infection. Universal maternal screening and passive-active immunoprophylaxis of newborns have reduced transmission of HBV, but the addition of antiviral therapy is necessary to further decrease immunoprophylaxis failure.
- Tenofovir, telbivudine, and lamivudine can be used safely in pregnancy without apparent teratogenicity or other harmful effects on mother or baby. But optimal outcome requires discussion of safety and the plan of care with the patient, obstetrician, and hepatologist.
- Most pregnant women with hepatitis C virus (HCV) infection have chronic disease, with no effects on the pregnancy or baby, but 3% to 5% transmit HCV to their child at the time of birth. All pregnant women at risk should be screened at the first prenatal visit. The safety and efficacy of treating pregnant women to prevent transmission to the fetus are not established; thus, treatment is not recommended for pregnant women.
Delivery and breastfeeding
The mode of delivery does not appear to have a significant effect on the interruption of vertical transmission of HBV.29 Cesarean delivery is not recommended by the US Centers for Disease Control and Prevention (CDC)2 or the American College of Obstetricians and Gynecologists.6 Breastfeeding is encouraged if the infant has received appropriate immunoprophylaxis.6
Coinfection with hepatitis D
Coinfection with hepatitis D virus (HDV) and HBV is associated with severe acute hepatitis30,31 and increases the risk of death by a factor of 10. The World Health Organization recommends testing for HDV in pregnant women who are HBV-positive.8
Prevention of HDV infection requires prevention of HBV. The treatment of HDV in pregnancy is supportive. Pegylated interferon is successful outside pregnancy but is contraindicated during pregnancy.32 In patients with fulminant hepatic failure and end-stage liver disease, liver transplant can be lifesaving.
Take-home points
- HBV infection during pregnancy is usually benign and not severe but can be associated with an increased risk of mother-to-child transmission and progression of liver disease in the pregnant mother.
- Prevention of vertical transmission of HBV is important to reduce the burden of chronic HBV infection. Universal maternal screening early in pregnancy and passive-active immunoprophylaxis of newborns are usually sufficient to prevent vertical transmission of HBV, but antiviral therapy is needed for highly viremic mothers to further reduce the risk.
- Antiviral therapy is also indicated for pregnant women with moderate to severe hepatitis or cirrhosis to prevent disease progression and liver failure.
- Telbivudine, tenofovir, or lamivudine can be used during pregnancy, but more data are needed on the long-term safety of fetal exposure to these agents.
HEPATITIS C
The global prevalence of hepatitis C virus (HCV) infection is 2% to 3%, with 130 to 170 million HCV-positive people, most of whom are chronically infected.33 The incidence of HCV during pregnancy is 1% to 2.4%, but 3% to 5% of infected mothers transmit HCV to their child at the time of birth.6,34 Women coinfected with HIV and HCV have twice the risk of perinatal HCV transmission compared with women who have HCV infection alone.6,34
HCV infection is usually asymptomatic and is discovered either by screening high-risk patients or during evaluation of persistently elevated aminotransferase levels. Acute HCV infection during pregnancy has been reported only rarely, and most pregnant women who are infected have chronic disease with no effect on the pregnancy or the infant.6,34
Treatment
The CDC recommends that all adults (including pregnant women) born between 1945 and 1965 undergo 1-time testing for HCV without prior ascertainment of HCV risk (strong recommendation, with moderate quality of evidence).35 The most important risk factor for HCV infection is past or current injection drug use.33 Additional risk factors are similar to those for nonpregnant patients.
Because of the benign effect of HCV on the pregnancy, treatment is not recommended. To decrease the risk of maternal-child transmission, it is prudent to avoid amniocentesis, scalp instrumentation, and prolonged rupture of membranes.6
There is no vaccine or immune globulin for prevention. HCV infection should not influence the mode of delivery, and it is not a contraindication to breastfeeding.34,36,37
HEPATITIS E
Every year, 20 million cases of hepatitis E virus (HEV) infection are recorded worldwide. These numbers include 3.3 million symptomatic cases and 56,600 deaths.38 HEV infection is most common in developing countries, and pregnant women traveling to these areas are at high risk of acquiring this infection, of developing fulminant hepatitis, and of death.39 Sporadic cases not associated with travel are increasingly reported in developed countries and are attributed to immunocompromised status (due to HIV or solid-organ transplant).38,40
Modes of transmission of HEV are mainly via fecal-oral contamination and by vertical transmission.41
Diagnosis
HEV infection can be diagnosed either by detecting IgM antibody with an enzyme-linked immunosorbent assay or by detecting HEV RNA in the blood using reverse transcription polymerase chain reaction testing.42
Treatment and prevention
Hospitalization should be considered for pregnant women. Ribavirin or pegylated interferon alpha or both are effective but are contraindicated in pregnancy because of the risk of teratogenicity.41,42 Urgent liver transplant can be a successful option in acute liver failure.
Prevention relies primarily on good sanitation, clean drinking water, and avoiding raw pork and venison. Boiling and chlorination of water inactivate HEV.39,40 Pregnant women should be advised to avoid travel to highly endemic areas.
