CDC Report: Down Syndrome More Common

I don't know how many of you have heard about this, but I found it quite interesting:

By THE ASSOCIATED PRESS
January 5, 2005 ATLANTA

(AP) -- Down syndrome in the United States is more common thanpreviously thought, at one case for every 733 live births, according to anew government report containing what are regarded as the most reliableestimates yet on the prevalence of 18 types of birth defects. Previously, Down syndrome, a type of retardation caused by a geneticmutation, was estimated to occur in a range of one in every 800 live birthsto one in every 1,000.The report, released Thursday by the Centers for Disease Control andPrevention, also found that cleft lip occurs in about one in every 1,000births, and cleft palate in about one in every 1,500.The report was celebrated by advocacy groups that help families affected bybirth defects. They noted that the new numbers are based on statewide data,while previous estimates were derived from selected clinics and hospitals.''Until now, there's been a real dearth of good, reliable, nationalstatistics on Down syndrome,'' said Suzanne Armstrong, spokeswoman for theNational Down Syndrome Society.The risk of Down syndrome increases with the age of the mother, from anestimated 1 in 2,000 among 20-year-old women to 1 in 100 for women age 40. Many women are having babies later in life, which might explain the higherrate in the new study.But because the new statistics were not collected in the same way as theold, it is not clear whether Down syndrome has really increased, Armstrongand others said.From 1974 until the mid-1990s, the government tracked birth defects througha system that relied on hospital discharge reports. But not all hospitalswere represented, and researchers said it was possible that theparticipating hospitals attracted more or fewer problematic births than thenorm. In 1997, the government collected data from all birth hospitals,clinics and referral centers in certain parts of the country.The new report presents statewide data for Arkansas, Hawaii, Iowa,Massachusetts, North Carolina, Oklahoma, Texas and Utah. It also has datafrom the metropolitan Atlanta area, the Central Valley in California and agroup southern Alabama counties. The statistics are for the years 1999 to2001.The 11 states account for about 22 percent of all live births in the UnitedStates each year and are a good representative sample, said Joann Petrini, astudy co-author and director of the March of Dimes' perinatal data center inWhite Plains, N.Y.The researchers included only 18 of the thousands of birth defects that havebeen identified by doctors and scientists. Missing are common birth defectssuch as clubfoot, hip dislocation and hypospadias, in which a boy's urinaryopening is on the underside of the penis instead of the tip. Spina bifidawas not included either, because health officials already have what theyconsider reliable estimates.