Study: CVS safer, more efficient than early amnio: associated with fewer congenital anomalies. (Large, Randomized Trial).

SAN Francisco -- Results of an international randomized trial suggest that chorionic villi sampling is safer and more efficient than early amniocentesis.

The study included 3,775 patients randomized to amniocentesis or chorionic villi sampling (CVS) at 12-14 weeks' gestation. The CVS procedures were more likely to be successful and easier to interpret. They also were associated with fewer cases of pregnancy loss, amniotic fluid leakage, and congenital anomaly, Dr. Laird Jackson said at the annual meeting of the Society for Maternal-Fetal Medicine.

When asked whether the findings overall should put an end to the practice of early amniocentesis, he responded, "That's what I'd say."

The new data support previous Danish and Canadian trial results showing an increased rate of congenital clubfoot in infants of women who underwent amniocentesis at 11 weeks' gestation.

The investigators intended to recruit women in the 11th week of gestation, but when the Danish and Canadian data came out, the protocol was modified and patients were not enrolled unless they were at least in the 12th week. The study participants, whose mean age was 37 years, included 334 pregnant women in the 12th week of gestation, 2,446 women in the 13th week, and 995 women in the 14th week.

A total of 265 women underwent testing in the United States, 234 in Canada, and the rest in Denmark, said Dr. Jackson, professor of ob.gyn. and medical genetics at Drexel University, Philadelphia.

Approximately 2% of patients in both the amniocentesis and CVS groups terminated their pregnancies due to abnormal test results. Women in the early amniocentesis group, however, were 50% more likely than women in the CVS group to have ...