Washing Away the Virus
SCIENTISTS BELIEVE THE KEY to helping the female partner get pregnant without transmitting HIV is a relatively simple laboratory technique called sperm washing. The procedure is used every day in conventional sperm banks and infertility clinics to boost the potency of sperm. With a centrifuge and other equipment, lab technicians separate sperm from the rest of the semen - removing extraneous cells and fluids. Some labs subject the sperm to a chemical obstacle course so that only the most active swimmers make it to the finish line, kind of like salmon leaping upstream to spawn. Once a sample is cleaned, the sperm are injected into the woman's uterus by artificial insemination.
Harvard HIV researcher Deborah Anderson, an associate professor of
obstetrics, gynecology, and reproductive biology at Harvard Medical School,
conducted extensive studies on sperm washing and found it highly effective
against HIV (her lab is completely independent of Kiessling's work).
Anderson says sperm washing can reduce the level of HIV in semen
"I don't think you can give 100-percent guarantees," Anderson says. "But what you can offer is numbers that say that by doing a sperm wash the couple is much better off, much safer, than trying to conceive on their own."
Anderson believes that HIV generally lurks in white blood cells and other
parts of the semen, not in the sperm cells. The question of whether sperm
cells carry HIV is still scientifically controversial. Some researchers
suspect that HIV may infect the sperm cells of men with advanced cases of
"Other labs claim [HIV] can actually adhere to the sperm," Kiessling says. "We haven't been able to detect that."
Sperm washing is not available to the American public, even though it's
been offered for a decade at San Paolo Hospital in Milan, Italy. Research
from the program has been published in leading international medical
journals, a sign that the Milan clinic does scientifically credible work.
As of this spring, Doctor Augusto Semprini has artificially inseminated more
than 470 women with washed sperm taken from their HIV-infected partners.
More than 250 women got pregnant, and 187 gave birth.
"No woman who has been inseminated has ever developed infection with HIV," Semprini says. "No child ever got infected. So we think the risk of infection by achieving pregnancy with our method is quite low."
Semprini says sperm washing for HIV is now offered at medical centers in the United Kingdom, Spain, and Switzerland. Despite the Italian success record,
the federal Centers for Disease Control and Prevention in Atlanta does not
condone sperm washing for HIV. Epidemiologist Scott Holmberg says other
researchers need to replicate the Milan results before the technique should
be widely used in the United States.
"My colleagues and myself have not yet seen this enough to feel real
comfortable. At least initially, it will be a gamble on the part of the
people using the technique," Holmberg says.
Organizers of the Assisted Reproduction Foundation freely acknowledge the
technique is experimental. The first group of six couples will be part of a
clinical trial to test the safety of Kiessling's protocol. But Kiessling
hopes to expand the study to serve as many people with HIV as needed. She
worries that many HIV-infected couples are taking their own, private risks
by making babies the traditional, unprotected way.
"I think about how many women have put themselves at risk of infection since I started thinking about this ten years ago. It's thousands and thousands of women," Kiessling says.
Semprini suspects that, with the exception of Ann Kiessling and a few
others, American infertility specialists are slow to offer help to
HIV-infected men because of an unrealistic belief that novel medical
techniques should present zero risk. In Italy, he says, doctors respect the
judgment of HIV-infected patients on whether or not to take a small risk in
order to have children. Semprini predicts that scientists will one day cut
the danger of infection to zero.
High-Tech May Lower Odds
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