Acquired immunodeficiency syndrome: epidemiology and significance for the obstetrician and gynecologist.

A retrovirus, variously named human T-lymphotropic virus type III or lymphadenopathy-associated virus, is now recognized as the etiologic agent of the acquired immunodeficiency syndrome. As of January, 1986, more than 16,000 cases of acquired immunodeficiency syndrome have been reported, and it is estimated that greater than or equal to 1 million Americans are now infected with human T-cell lymphotropic virus/lymphadenopathy-associated virus. Most cases of overt acquired immunodeficiency syndrome still fall within well-defined "high-risk groups," that is, homosexual or bisexual men, intravenous drug users, recipients of transfused blood or blood components, and persons with hemophilia. Also at risk are heterosexual partners of persons who have overt acquired immunodeficiency syndrome or who are at risk for acquired immunodeficiency syndrome, as are children born to mothers who either have acquired immunodeficiency syndrome or are members of a "high-risk group." Transmission of the virus may occur via sexual contact, via parenteral exposure to contaminated blood products, or from an infected mother to her child. Of special concern to the practicing obstetrician are recent reports suggesting bidirectional heterosexual transmission, transmission via artificial insemination, and perinatal transmission. In addition, the isolation of human T-cell lymphotropic virus/lymphadenopathy-associated virus from human breast milk raises concerns regarding potential transmission by this route.