Second-trimester maternal serum double-test screening for down syndrome

Abstract EN

Objective : The purpose of the study was to determine the detection rate of Down syndrome using the double- test; Alfa-feto protein and human chorionic gonadotropin.

Methods : Five thousand three hundred and thirty pregnant women below the age of 35, were screened between November 1998 and October 1999 at Birmingham Women's Hospital, U.K.

They were singletons and without risk factors for chromosomal abnormalities.

Results : Two hundred and twenty patients (4.1 %) were initially classified as screen positive.

After revision of gestation by ultra-sound, 159 (3 %) were true screen positive.

Eight were affected by Down syndrome and all selected pregnancy termination after counseling.

The odds of being affected given a positive screen result was 1 in 33.

Three affected pregnancies were missed.

The detection rate was 57 %.

Conclusion : The study of second- trimester double-test screening for fetal Down syndrome was acceptable to be usedfor all pregnant women below the age of 35.