There's more than one way for HIV positive couples to attempt a safe pregnancy. In theory,
procedures like sperm washing are fairly straightforward -- collect the semen of an HIV-positive man
away the parts of it that carry the virus. In practice, though, the undertaking raises complicated
Sperm washing is actually a common technique. It's been used for years by infertility clinics to
boost the potency of a man's semen when trying to help his female partner conceive. It takes
advantage of the fact that sperm are small and heavy, and can move like tadpoles. The semen is put
in a test tube which is then spun in a centrifuge to separate the sperm from the other cells and
fluids. The non-sperm part of the semen is removed, and each fraction is tested for HIV. If both
parts are negative, the isolate sperm are covered with a new solution, which the healthiest cells
will swim their way into. If no virus is found in a second test on the sperm, they can be used to
fertilize the woman's egg cells.
There are currently three ways to attempt pregnancy using washed sperm.
A common method used for years is intravaginal insemination, which involves holding a
cervical cap full of live sperm near a woman's cervix and allowing them
to swim into the uterus. Dr. Ann Kiessling, director of the Assisted
Reproduction Foundation in Boston, says this procedure may be safe, but hasn't been tried.
But, she adds, the safest method is in vitro fertilization,
which only exposes the woman to fertilized eggs, and not to live sperm
A third method, called "intrauterine insemination," or IUI, has been
used by HIV couples in Italy, the UK, Spain and Switzerland. It involves
inserting a catheter filled with washed sperm directly into the woman's
uterus. Dr. Augusto Semprini, an Italian researcher who first applied
IUI to HIV cases, claims to have achieved more than 250 pregnancies
without a single viral transmission to either mother or child. But Dr.
Kiessling remains cautious. IUI, she says, can leave the woman exposed to any trace cells that aren't
filtered out in the washing process or detected by microscopic
evaluation. And, she adds, it requires about ten times as many sperm
cells as IVF, and can be an uncomfortable, invasive procedure.
All three of these methods rely on the belief, shared by many
researchers, that HIV lurks in white blood cells and the fluid parts of
semen. That would make sperm-washing a potentially safe way to
impregnate an HIV-negative woman with the sperm of her HIV-positive
partner. Some scientists believe that sperm-washing can reduce the level
of HIV in an infected man's semen by 100,000-fold.
But that's not enough to convince the Centers for Disease Control and
Prevention in the United States, and the legality of IUI stands on shaky
ground in the U.S., where it's illegal in some states to transfer
HIV-infected blood or tissue from one person to another. Those laws
could be interpreted to include methods like this one, that assist in
Beyond the legal questions are the scientific ones. Sperm washing
appears to effectively separate sperm cells from infectious agents in
semen, but exactly how thorough it is hasn't been quantified. Some
researchers also wonder whether HIV can be carried in the actual sperm
cells of men who have been infected for a long time. If that were the
case, then separating those cells from white blood cells and other
fluids would still leave the mother and her child open to infection.
Sperm-washing combined with IUI did result in one man passing the
virus to his partner in this country. The woman sued her doctor, though
it remains unclear whether her infection was caused by the procedure.
Health care professionals willing to undertake the sperm-washing venture
are quick to remind their patients that it is only a risk-reduction
method, and that no procedure is entirely risk-free.
But those cautionary words can be forgotten amidst the flurry of
anticipation for couples who, not so long ago, thought they would never
be able to consider raising a family. As drug therapies allow people
infected with HIV to live longer, the demand for reproductive strategies
is expected to rise. In Europe , doctors are fielding an increasing
number of inquiries about how to conceive children without passing on
the virus. They may find that convincing anxious parents of the lack of
certainty in the process is as challenging as carrying it out.