Hepatitis C virus (HCV) is a bloodborne pathogen that primarily targets the liver, causing inflammation and potentially leading to long-term chronic infection. The increasing number of infections among individuals of reproductive age has made screening for this virus during pregnancy a public health priority. Identifying HCV infection in expectant parents promotes maternal health and manages the risk of transmitting the virus to the baby. Universal screening is now a standard component of prenatal care to ensure timely diagnosis and linkage to treatment.
Current Screening Guidelines and Procedures
Screening for Hepatitis C during pregnancy has recently shifted from a risk-based approach to a universal recommendation. The Centers for Disease Control and Prevention (CDC) and the American College of Obstetricians and Gynecologists (ACOG) now advise that all pregnant people be tested for HCV during each pregnancy. This change recognizes the rising prevalence of the virus and that many infected people may not have traditional risk factors.
The screening process is typically a two-step procedure initiated during the first prenatal blood assessment. The initial test looks for HCV antibodies, which indicate a past or current exposure to the virus. A positive antibody result means the person has encountered HCV, but it does not confirm an active infection.
If the antibody test is positive, a second test is necessary to determine the current status of the infection. This confirmatory test is a Nucleic Acid Test (NAT), often called an HCV RNA test or viral load test. A positive RNA test confirms the presence of the active virus and a chronic infection, which carries a risk of transmission to the infant. A negative RNA test suggests the infection has cleared, or the initial antibody result was a false positive.
Understanding Vertical Transmission Risk
The primary reason for universal screening is to identify individuals whose active infection poses a risk of mother-to-child transmission (MTCT), also known as vertical transmission. For mothers with a confirmed chronic HCV infection (HCV RNA-positive), the risk of transmission to the baby is generally low, estimated at approximately 6% to 7%. This transmission typically occurs late in the pregnancy or during labor and delivery, rather than through the placenta early in gestation.
Several factors increase the probability of vertical transmission. A very high maternal viral load, specifically an HCV RNA level greater than 10\(^{6}\) copies per milliliter, is associated with a greater risk of the virus passing to the infant. Co-infection with the Human Immunodeficiency Virus (HIV) can also double the transmission risk, raising the likelihood to around 11% to 12% in some studies.
Certain obstetric practices can also elevate the risk of the baby being exposed to maternal blood during delivery. Procedures such as internal fetal monitoring or the early artificial rupture of membranes have been linked to higher rates of transmission. Health care providers focus on managing the delivery to minimize these exposures, though the mode of delivery itself is usually not a factor in prevention.
Post-Diagnosis Management and Infant Follow-Up
When a pregnant individual is diagnosed with an active HCV infection, management focuses on monitoring maternal liver health and coordinating care for the infant after birth. Current standard of care involves deferring treatment with Direct-Acting Antivirals (DAAs) until after delivery and the cessation of breastfeeding. This is due to a lack of sufficient safety data regarding the effects of these medications on the developing fetus.
The diagnosis of HCV alone does not necessitate a scheduled Cesarean section; the mode of delivery should be based on standard obstetric indications. Providers manage the labor to avoid procedures that increase the baby’s exposure to maternal blood, such as prolonged rupture of membranes or the use of internal scalp electrodes. The care plan includes linking the mother to a specialist to begin curative DAA therapy soon after the baby is born.
Breastfeeding is generally considered safe for mothers with HCV and is not contraindicated unless the nipples are cracked or bleeding, which could expose the infant to infected blood. The primary goal of post-diagnosis care is to cure the mother’s infection and ensure the exposed infant receives proper follow-up testing.
Infant follow-up involves a specific testing schedule because maternal antibodies against HCV can pass through the placenta, remaining in the baby’s bloodstream for many months. To avoid a false positive result based on these transferred antibodies, the initial screening with an HCV antibody test is delayed until the child is 18 months of age or older. Alternatively, a more definitive test using a Nucleic Acid Test (NAT) for HCV RNA can be performed as early as two to six months of age to determine if the virus was transmitted. This early testing is crucial for the timely linkage of an infected child to specialized pediatric care.