The purpose of this study is to determine whether the oral administration of daily selenium supplements to HIV-1 positive pregnant women: enhances immune status and reduces the HIV-1 viral load at six months postpartum, reduces the risk of lower genital shedding of HIV-1 infected cells at 36 weeks of gestation, and reduces the risk of mastitis at six weeks postpartum, compared to placebo.

We are recruiting pregnant women who are infected with HIV and assign them to receive selenium or placebo. All women will be given standard prenatal care, including nevirapine for the prevention of mother-to-child transmission and prenatal multivitamin supplements. We will examine the effect of the selenium supplements on intermediate outcomes predictive of the risks of transmission of HIV and to disease progression.

Inclusion Criteria:

• HIV-1 Infected women between 12 and 27 weeks of gestation

Exclusion Criteria:

• Women with clinical AIDS defined according to WHO Criteria