Link found to assisted reproduction.(human in vitro fertilization and rare birth defect risk )

2002 DEC 19 - (NewsRx.com & NewsRx.net) -- Scientists from Johns Hopkins and Washington University School of Medicine in St. Louis have discovered that in vitro fertilization (IVF) appears to be associated with a rare combination of birth defects characterized by excessive growth of various tissues.

After studying data from a national registry of patients with Beckwith-Wiedemann syndrome (BWS), the researchers found that IVF-initiated conception was six times more common than in the general population. The findings are slated for the January 2002 issue of the American Journal of Human Genetics.

Children born with BWS, which may predispose them to Wilms tumor, hepatoblastoma, neuroblastoma and other cancers, would likely represent only a tiny fraction of babies conceived via IVF if the findings are confirmed, the researchers emphasized. The results should stimulate further investigation, not change parents' decisions, they said.

"This analysis should not affect people's decisions about whether to have IVF, because our findings still need to be validated," said Andrew Feinberg, MD, King Fahd Professor of Medicine at Johns Hopkins and a member of the school's McKusick-Nathans Institute for Genetic Medicine. "What is learned might improve the health of all children."

"At this point, we simply have a strong association between BWS and IVF," adds Michael R. DeBaun, MD, MPH, assistant professor of pediatrics at Washington University School of Medicine and a staff physician at St. Louis Children's Hospital. "We need additional data to verify our findings, and if confirmed, to understand why there is an association."

BWS occurs in about 1 in 15,000 births overall. Currently, IVF is not thought to result in birth defects at a higher rate than natural conception, according to the Society for Assisted Reproductive Technology.

"While our study has its limitations, we believe it's time to begin looking at these issues more formally," said Feinberg, who has been studying imprinting's role in disease, particularly cancer, for some time.