Viral infections in pregnancy.

The responsibility of the physician for viral infections in pregnancy has changed dramatically in the last 15 years. Genital herpes infections have become much more frequent, and the recognition of these infections in women near term is particularly important. Cytomegaloviruses have been found to be the most commom cause of congenital infection, but no satisfactory methods are available for prevention or treatment. Varicella is now recognized as a teratogen when infection occurs in the first 4 months of pregnancy. It can also cause severe generalized disease in the newborn when infection takes place in the last few days of gestation. Hepatitis B infections are becoming more frequent in many populations, and this virus can transmit to the child, particularly when maternal infection occurs in the last trimester. Venezuelan equine encephalitis virus has been found to be a teratogen. This must be considered in southern states such as Florida and Texas, as well as in Central and South America. Rubella, fortunately appears to be coming under control with the intensive use of serodiagnosis and vaccines in the United States.