Hepatitis C Screening Recommended During Pregnancy

The estimated prevalence of antenatal Hepatitis C (HCV) infection is low in the USA, about 1%-2.5%, although some have suggested that it’s as high as 4% and some have recommended against screening all pregnant women for HCV, citing a lack of data on the cost-effectiveness of universal screening.

New guidance from the Society for Maternal-Fetal Medicine (SMFM, Washington, DC, USA) recommends a thorough testing regime for pregnant women at high risk for the hepatitis C virus (HCV) and a prescriptive set of recommendations on screening workups for this disease. The guidance was reviewed and endorsed by the American College of Obstetricians and Gynecologists (ACOG, Washington, DC, USA).

The guidance recommends HCV prenatal testing for women with certain high risk factors, such as illegal drug use, unregulated tattoos, those on long-term hemodialysis or a history of incarceration, or who received blood products from a donor who eventually tested positive for HCV. Women who received transfusions or organ transplants prior to July 1992 and clotting factor concentrates produced before 1987 should also get screened. Screening for high risk patients should take place at the first prenatal visit and even if this initial test is negative, a second screening may be warranted at a later stage of the pregnancy if new or persistent HCV factors arise, such as the use of intranasal or injected illicit drugs.

Clinicians use anti-HCV antibody tests to screen for this disease. Positive results can mean one of several things: an acute or chronic HCV infection, a past infection that has since resolved, or a false positive result. SMFM and ACOG recommend that a quantitative nucleic acid test for HCV RNA follow any positive result for HCV antibodies. In other screening recommendations, SMFM and IDSA advised that clinicians follow up with HCV RNA testing in patients exposed to HCV within a 6-month period who have tested negative for anti-HCV antibodies. This is necessary because these antibodies might not have become detectable at the time of initial testing.

HCV-positive pregnant women also should get tested for sexually transmitted diseases such as HIV, syphilis, gonorrhea, chlamydia, and hepatitis B virus. Patients who request invasive prenatal diagnostic testing should be notified about the limited data available on the risks of vertical transmission, and that amniocentesis is a preferred method over chorionic villus sampling. In other recommendations, the authors advised against relying on cesarean delivery to indicate HCV.

Brenna Hughes, MD, MSc, a Maternal-Fetal Medicine Specialist and the guidance’s lead author, said, “The rationale for the timing of the diagnosis of infants relates to the fact that maternal antibodies can persist for months in infants leading to false positive diagnoses. It is also possible that an infant can clear virus from the mother so the requirement for HCV RNA twice after the age of one month is to avoid false positive diagnoses.” The guidance was published in the November 2017 issue of the American Journal of Obstetrics and Gynecology.

Related Links:
Society for Maternal-Fetal Medicine
American College of Obstetricians and Gynecologists