Cultural factors impact amniocentesis decision: prospective study suggested.(Obstetrics)

LOS ANGELES -- Social, cultural, and demographic factors seem to exert a stronger influence than numeric risk on a woman's decision to undergo amniocentesis following ultrasound and a maternal serum screen positive for Down syndrome, according to a retrospective study tracking records of nearly 6,000 California women.

Women most likely to undergo amniocentesis after a positive expanded alpha fetoprotein (AFP) screen were non-Hispanic, aged 29-36 years, childless or primiparous, with no history of previous pregnancy loss, Kristin M. Borsack explained during the annual meeting of the American Society of Human Genetics.

No correlation was found between a woman's statistical risk of bearing a child with Down syndrome and the decision to undergo amniocentesis, meaning that a woman with an estimated 1 in 10 chance of having an affected baby was about as likely to undergo amniocentesis as a woman with an estimated 1 in 100 chance.

All subjects included in the study had at least a 1 in 190 chance of having a baby with Down syndrome, based on the cutoff for a positive AFP test set by the state of California.

Ms. Borsack, who is a genetic counselor, tracked records of all 5,979 women with a positive test result from Genzyme Genetics (a provider of genetic testing and counseling services) who received genetic counseling between March 2001 and January 2003.

Overall, 51.2% of subjects elected to undergo amniocentesis.

Ethnicity was correlated most strongly with the decision. Hispanics who re quested genetic counseling in Spanish were least likely to undergo amniocentesis, at 35%.