Human immunodeficiency virus(3) herpes simplex virus(3) Viral infections.(2) cytomegalovirus(2) Pregnancy(2) COVID-19(2) Maternal-to-child transmission(2) Viral hepatitis(2) vaccination.(1) Preterm premature rupture of membranes.(1) Postexposure Prophylaxis(1) Hepatitis B virus(1) Perinatal(1) prevention(1) hepatitis B(1)