Baltimore Sun
16 November 2002

Study ties in-vitro fertilization to genetic disorder
Finding called compelling, but more research needed

By Jonathan Bor
Sun Staff

Babies conceived by in-vitro fertilization may be at increased risk for a rare genetic disorder that predisposes them to cancer, scientists reported yesterday.

Scientists from the Johns Hopkins School of Medicine and Washington University in St. Louis tracked children born with Beckwith-Wiedemann Syndrome and found that an unusually large percentage were conceived by IVF.

In the United States, fewer than 1 percent of all births were due to in-vitro. But when doctors tracked 63 children born with the genetic disorder - babies who were entered into a Beckwith-Wiedemann registry after June 2001 - they discovered that more than 4 percent were in-vitro babies.

Dr. Andrew Feinberg, a Hopkins genetics professor, said the statistical association does not mean that in-vitro can trigger the genetic alterations responsible for the defect. But he said the finding is compelling and should lead to further study.

No tracking system

There is no central registry to track birth defects among babies conceived through assisted reproductive technologies, even though about 40,000 babies in the United States alone were conceived last year with IVF.

"The only way you're really going to get a sure answer is to collect information on a large enough number of IVF offspring," Feinberg said. "This hasn't been done systematically."

He added, "This analysis should not affect people's decisions about whether to have IVF because our findings still need to be validated."

The study is due to be published next week in the online version of the American Journal of Human Genetics.

Beckwith-Wiedemann Syndrome, occurring in about 1 in 15,000 births, causes children to be born abnormally large, with large tongues and with poor closures of the abdominal wall. This can produce hernias that must be surgically repaired.

Additionally, the children are at high risk for developing cancers of the kidney, liver and other tissues before puberty.

Earlier study

Last spring, a study published in a national journal found an elevated rate of birth defects among in-vitro babies, but the study was considered too small to be conclusive.

Dr. Philip I. McNamee, past president of the Society for Assisted Reproductive Technology, says it is difficult to draw any conclusions about birth defects among IVF children because there is no tracking system.

McNamee, a professor at the University of Hawaii in Honolulu, said he hadn't read the Beckwith-Wiedemann study but was intrigued. "You have to be very careful drawing conclusions from this sort of data," he said.