Risk of vertical transmission of chronic viral infections after invasive prenatal procedures.

Objectives: Invasive prenatal procedures including amniocentesis, chorionic villus sampling (CVS) can be prenatally indicated for diagnostic purposes. Chronic viral infections with Human Immunodeficiency Virus (HIV), hepatitis C virus (HCV), hepatitis B virus (HBV) are not uncommon in women of reproductive age. The aim of this narrative literature review is to provide guidance on the best clinical practice in antenatal invasive testing and fetal surveillance in pregnancies with HIV, HCV, HBV and treponema pallidum infected women.

Material And Methods: A review of the literature was conducted in the database of PubMed to select full-length articles published in peer-reviewed journals between 1990 and 2020. The keywords along with respective combinations included in the search strategy were invasive testing, prenatal diagnosis, amniocentesis, chorionic villus sampling, cordocentesis, fetoscopy, chronic viral infections, hepatitis B, hepatitis C, HIV, treponema pallidum, syphilis, vertical transmission, MTCT.

Results: For patients with hepatitis B infection, it is important to assess the HBeAg status and HBV DNA levels and for those patients with high viral load, antiviral therapy (Tenofovir) for a few weeks may be needed to reduce the viral load prior to the invasive procedure. In women positive for HCV, the viral load and HIV status should be assessed to establish the risk of vertical transmission; while for patients with HIV, highly active antiretroviral therapy administration and low viral load are predictive for reduced vertical transmission even after performing an invasive procedure. In all cases invasive procedure should be replaced by non-invasive prenatal testing if this is a feasible alternative and when invasive testing is indeed required, transplacental passage should be avoided.