Health News

Keeping Pace With Infertility

June 28, 2001 -- Some infertile couples who chose sperm injection into the egg to help them conceive may get the same results with the more conventional approach of mixing sperm and egg in laboratory dishes.

Sperm injection, known by the acronym ICSI (pronounced ick-see), has been in use since the early '90s as an option to in vitro fertilization (IVF) for couples with so-called male-factor infertility, in which an abnormality prevents sperm from being able to penetrate an egg and fertilize it.

In ICSI, specialists essentially give a sperm a ride into a preselected egg by injecting it through a needle.

The success of ICSI has led many experts to wonder if people with other types of infertility might also be better able to conceive with ICSI than with IVF. Some centers routinely offer ICSI to anyone with a fertility problem who is a candidate for IVF on the theory that it will maximize their chance of a pregnancy.

But a study in the June 30 issue of The Lancet suggests that may be a false assumption.

The study of 415 couples with non-male-factor infertility found higher pregnancy rates per cycle with IVF compared with ICSI (33% vs. 26%).

According to the authors, led by Siladitya Bhattacharya, MD, of Aberdeen University in the U.K., the study implies there may actually be "a marginal disadvantage" of ICSI when used in cases of infertility that are not related to male factors. However, they further add that their study cannot rule out the possibility that certain subgroups of patients who do not have male-factor infertility may have a better success rate with ICSI than with IVF. Those subgroups may include older women and those with poor ovarian function.

In a commentary accompanying the study, Sergio Oehninger, MD, an infertility expert at Eastern Virginia Medical School in Norfolk, says the findings "strongly support the concept that ICSI offers no advantage in terms of clinical outcomes over standard IVF in cases of non-male-factor infertility and unexplained infertility."

But a fertility expert who was not affiliated with the study says people should be careful about interpreting the results.

"The success rates associated with ICSI are very dependent on the individual doing [the procedure]," says Mark Perloe, MD.

He says the pregnancy rate in the British study is "very low" compared to what many experts in the U.S. would expect from ICSI procedures.

"The materials ... may be different from lab to lab and in a situation where you see lower pregnancy rates one wonders whether there is an issue with the lab that may translate either to less experience or ... perhaps technique differences," says Perloe, who is the director of reproductive endocrinology, infertility, and in vitro fertilization at Georgia Baptist Medical Center in Atlanta.

Bhattacharya and colleagues maintain that ICSI shouldn't be offered to anyone who might otherwise conceive successfully with IVF. They believe ICSI is frequently being used in cases where it isn't indicated based not on evidence that it is better than IVF but on the fact that the technology behind it is newer.

A second study in the same issue of The Lancet should be reassuring to couples who do use ICSI. The study by Alastair Sutcliffe, MD, of University College in London, finds no evidence that children conceived through sperm injection have more brain development problems or overall health problems than children conceived through IVF. Experts have expressed concern that sperm incapable of penetrating an egg on their own may be defective to begin with, putting the resulting child at risk for various genetic defects and abnormalities.