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Patients Are Skeptical
Assisted reproduction specialist Eric Surrey, MD, says it is increasingly clear that for patients with a good prognosis for conception, single-embryo transfer may be preferable to multiple transfers. But he adds that convincing infertile couples of this has been difficult.
"In this country, insurance almost never pays for in vitro fertilization, so maximizing the chances of pregnancy the first time around is a big concern," says Surrey, who is president of the American Society for Reproductive Medicine.
"And couples who don't have children often see twins as a desirable outcome. They look at it as two for the price of one, and when we discuss the risks it seems like a lot of what we say doesn't get heard."
Surrey and colleagues at the Colorado Center for Reproductive Medicine recently published a study on single transfers of five-day-old embryos. The researchers achieved a 61% ongoing pregnancy rate with the single-embryo transfers.
"Even though we offered economic incentives for participating in the study, we still had a hard time recruiting patients for it," Surrey tells WebMD.
U.S. Population Different
The average age of the women who took part in the Swedish study was 30. That is far younger than the typical IVF patient in the United States, and the Swedish women were also less likely to have undergone other assisted reproduction procedures, IVF specialist Owen K. Davis, MD, tells WebMD.
In an editorial accompanying the study, Davis questions the relevance of the Swedish findings for infertile women in the United States.
"It is common practice in the United States to treat young infertile women with 'low-tech' options such as ovulation induction combined with intrauterine inseminations, often for several cycles, before proceeding to in vitro fertilization," he writes.
He adds that women who fail these low-tech treatments may be poor candidates for the single-embryo IVF approach.
Davis tells WebMD that embryo transfer guidelines in the United States were recently changed to urge doctors to consider single-embryo transfers for good-prognosis IVF patients, such as young women.
"Multiple-birth pregnancies are still a significant problem with IVF," he tells WebMD. "The vast majority of twins do just fine, but the risk is considerably higher than for single-birth pregnancies. Having babies one at a time is safest."
SOURCES: Thurin et al., The New England Journal of Medicine, Dec. 2, 2004; vol 351: pp 2392-2402. Christina Bergh, MD, PhD, Institute for Health of Women and Children, Goteborg, Sweden. Eric Surrey, MD, medical director, Colorado Center for Reproductive Medicine; president, American Society for Reproductive Medicine. Owen K. Davis, MD, Center for Reproductive Medicine and Infertility, Weill Medical College of Cornell University, New York; immediate past president, Society for Assisted Reproductive Technology.