Fertility treatments can be done safely and effectively in couples where the man is infected with the AIDS virus and the women isn't, according to a new review of past studies.

Over the last 2 decades, researchers have improved methods of "washing" the semen of men infected with HIV, the virus that causes AIDS. Unwashed semen could pass HIV to the woman or their baby.

"I think the procedure is getting safer and safer," said Dr. Deborah Anderson, a scientist at the Boston University School of Medicine who studies HIV. She was not involved in the current research, but she told Reuters Health that washing the man's semen lowers the risk of transmission enough that "it's an acceptable ... procedure for couples that really want to have children."

In the new review, published in the journal Fertility and Sterility, researchers from the Evandro Chagas Clinical Research Institute in Rio de Janeiro, Brazil looked at 17 earlier studies involving a total of about 1,800 couples in which only the male partner had HIV.

In each of the studies, researchers performed one of two common types of fertility treatments after washing the semen. Then they recorded how often women became pregnant after the procedures. They also monitored the women and any babies they had as a result of the procedures, to see whether HIV had been passed on from the semen.

About a third of the women had a procedure in which a single sperm is injected into a single egg; then the fertilized egg is placed into the woman's womb. This kind of fertility treatment is assumed to be safer for couples in which the male partner has HIV because it is easier to ensure that the sperm being used does not have the HIV virus.

The rest of the women had sperm injected directly into the womb, when their eggs were most likely to be there.

Ultimately, roughly half the women became pregnant, and about 80 to 85 percent of the pregnancies resulted in the birth of a baby.

The success rates for pregnancy were comparable to what has been shown in other studies of fertility treatment in couples without HIV. If anything, couples in the current study may have been more likely to get pregnant using fertility treatments because many of them had no underlying fertility problems, the authors say.

None of the women in the study, or babies that were born after fertility treatments, tested positive for HIV. However, in a few of the studies in which researchers tested semen after it was washed, between two and eight of every 100 samples tested positive for HIV - indicating that it still may be possible, if unlikely, for the virus to be passed either to the woman or to the fetus.

However, the findings are "very reassuring," according to Dr. Elizabeth Ginsburg of the Brigham and Women's Hospital Center for Reproductive Medicine in Boston.

Ginsburg, who was not involved in the study, said that even if some of the samples did test positive for HIV, the amount of the virus was probably so small that it wasn't likely to be passed to the mother or baby. In addition, she said, HIV transmission requires some sort of trauma to the woman's body because the virus is passed from semen to blood, and although there's a chance of that in intercourse, it's not likely in fertility treatment.

Despite mounting evidence of its safety, fertility procedures are not very common in couples in which the male partner has HIV. In part that's because the procedures aren't often covered by insurance, Ginsburg said. Although some fertility procedures may be as inexpensive as $1,000, others run many times higher.

"One of the things that is a shame is that when couples can't afford fertility treatment, they're stuck with the other option, which is having timed intercourse, and that puts the woman at risk," Ginsburg said.

Anderson said a new option for these couples might become available in the future — medications that the woman can take to avoid getting the virus from her partner who has HIV. 

And, "if the mom doesn't get it, the baby's not going to get it," she said. "I think that's going to be the future of this field."

So far, only a couple of early studies have been done on the drugs' effectiveness at preventing transmission of the virus, and for now, Anderson said, fertility treatment is the safest possible option for these couples.