Viral hepatitis in pregnancy is a very frequent problem and has numerous implications in the field of maternal-fetal medicine. For a pregnant woman it is very important become aware of any contact with the hepatitis A, B and C viruses because they can be transmitted to the fetus through various channels: for example the placental barrier, the birth canal and breastfeeding (only in the case of hepatitis B and C).
For this it is necessary that the future mother undergoes specific tests through which it is possible to identify the viruses responsible for the infection. In the most modern protocols of assistance in pregnancy, a HbsAg control, which allows detection of the hepatitis B virus, through a blood test which, if positive, demonstrates the infectious capacity of the woman.
This exam it should be performed at the beginning of pregnancy and repeated between the 33rd and 35th week of gestation to prevent possible transmission of the virus to the newborn during delivery. The HBsAg research has the advantage of identifying mothers with hepatitis B (the most fearful from the point of view of the risk of transmission to the fetus), and women who are healthy carriers of the virus.
The hepatitis B and C viruses have very similar characteristics to each other and differ markedly from the hepatitis A virus both in terms of clinical course and prognosis. If contracted during pregnancy, hepatitis B and C can be very dangerous for the fetus.
Maternal-fetal transmission can occur throughout the course of gestation, although in most cases it occurs during childbirth. The two pathologies in pregnant women manifest themselves with clinical characteristics not very different from those of non-pregnant women. About 10% of patients she does not develop the disease but becomes a healthy carrier often without being aware of it, a source of contagion not only for the fetus but also for the people around it. The passage of the virus through the placenta can occur in all stages of pregnancy, although the risk of infection for the fetus is particularly high when maternal hepatitis occurs in an acute form in the last trimester of pregnancy.
The virus, as already mentioned, can be transmitted to the fetus even at the time of delivery. Another source of transmission, albeit less frequent, can be represented by breastfeeding as it appears that HBsAg is present in milk in about 70% of cases. However, for oral transmission to occur, the virus must have a very high viral load. The risks to the child from contact with the virus can be very serious: in most cases the child will become a chronic carrier, but it is also possible that he will develop mild forms of the disease or, in the most severe cases (fortunately also rare), severe forms of liver disease (liver disease).
It must also be said that the B virus has been associated with the onset of cirrhosis and hepato-cellular carcinoma and a very serious risk for the newborn is precisely that of developing these types of diseases. All children born to HBsAg positive, i.e. potentially infected, mothers are subjected to preventive treatment with immunoglobulins and vaccine within 12 hours of birth: the association of the vaccine with gammaglobulins makes it possible to prevent infection of the newborn in 90-95% of cases and allows the mother to breastfeed the child without risk of transmission of the virus.
As for the mother, prevention is done only with immunoglobulins. Hepatitis A in pregnancy is very rare as is the possibility of the infection being transmitted to the fetus. However, if maternal infection occurs acutely in the third trimester of gestation, the risk of preterm birth is higher. In the event that the mother also contracts the infection when the time to give birth approaches, the virus can be transmitted to the newborn through the birth canal. In case of infection, therapy involves the administration of immunoglobulins to both the mother and the newborn and breastfeeding, if the mother's conditions allow it, is not contraindicated. The course of the disease is similar to that of non-pregnant women and can include fever, asthenia, arthralgia and jaundice while it can have more severe symptoms in women with a pre-existing malnutrition condition (this is what often occurs in underdeveloped countries) . The hepatitis A virus usually has a modest clinical picture in children and more severe in adults. As the main preventive measure against hepatitis A doctors recommend get the vaccine before planning a pregnancy
Beatrice Spinelli
