Yes, they can. Though an HIV-infected mother can pass the virus to her child during pregnancy, at the time of birth, or when breast-feeding the infant, medical treatment of both the mother and her infant can reduce the chances of this happening. HIV infection in both parents--that is, if the father is infected too--does not appear to affect the likelihood of having an HIV-infected baby.

HIV-infected women who need antiretroviral therapy (ART) to treat their own disease should start or continue to receive it during pregnancy. Even if women do not yet need ART to treat their own disease, they should receive it during pregnancy. The goal is to lower the mother's HIV viral load (the concentration of HIV in her blood) as much as possible to prevent infecting her fetus. The lower the mother's viral load during pregnancy and birth, the lower the risk of infecting her baby. A baby's chances of being born with HIV are only 2 in 100 when the mother has a viral load so low that it's undetectable.

Even when the mother's viral load is undetectable, a cesarean section can further reduce the risk of HIV transmission during labor and delivery.

After delivery, the infant should receive ART, for 4 weeks. In addition, the mother should avoid breast-feeding her baby to prevent transmitting the virus through her breast milk.

Doing all these things can reduce the risk of a mother passing HIV to her baby, from 25% to less than 2%. But passing the virus to the baby is still possible.

For their own peace of mind, HIV-infected couples wanting to have children should receive counseling, if possible, before making a decision. During counseling sessions, they should ask about the likelihood that they will survive long enough to effectively parent. They should learn how to deal with the possibility that their infant may become HIV infected. And they should learn how to cope if members of their family or community judge and stigmatize their child.

(See also: Can a couple in which one person is HIV positive and the other person isn't conceive a baby without passing the virus to the uninfected partner? (http://www.hiv.va.gov/ptfaq-2007-02-14) )