Maternal serum screening for birth defects: results of a Connecticut regional program.
Second trimester maternal serum screening provides a method to identify pregnancies at high risk for fetal Down's syndrome, trisomy 18, open neural tube defects, and a variety of other chromosomal and nonchromosomal fetal anomalies. Results are presented for a regional program to identify high-risk pregnancies using alpha feto-protein (AFP), human chorionic gonadotropin (hCG), and unconjugated estriol (uE3) analyses (triple marker testing). A total of 27,140 women received screening. Using a midtrimester Down's syndrome risk of 1:270 to define the high-risk group, 5.26% of women of all ages were screen-positive for Down's syndrome resulting in the eventual detection of approximately 72% of the affected fetuses. The detection rate for patients under 35 at estimated date of delivery was 61% and for women 35, or older, the detection rate was 100%. A separate protocol to screen for trisomy 18 identified 0.2% of pregnancies, with 38% of the trisomy 18 cases present in this group. Over 3% of women screen-positive for Down's syndrome or trisomy 18 had a serious fetal chromosome anomaly. In addition, 2.89% of women had an elevated AFP (greater or equal to 2.0 multiples of median). This component of the screening resulted in the identification of 86% of the neural tube defects, 75% of the ventral wall defects, and also some of the other various fetal anomalies present in the screened population. Since both laboratory and clinical data are combined to generate patient-specific risks, there is a need for quality control elements that go beyond that normally required for a clinical laboratory alone. We stress the need for comprehensive follow-up programs to evaluate screening programs and maintain high quality.
Benn
P A
PA
Department of Pediatrics, University of Connecticut School of Medicine, Farmington 06030-6140, USA.
Horne
D
D
Craffey
A
A
Collins
R
R
Ramsdell
L
L
Greenstein
R
R
D015415:Biomarkers / Q000097:blood; D006063:Chorionic Gonadotropin / Q000097:blood*; D000013:Congenital Abnormalities / Q000517:prevention & control*; D003237:Connecticut; D004964:Estriol / Q000097:blood*; D005260:Female; D006801:Humans; D008403:Mass Screening; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011296:Prenatal Diagnosis / Q000379:methods*; D015397:Program Evaluation; D012307:Risk Factors; D000509:alpha-Fetoproteins / Q000032:analysis*
D015415:Biomarkers; D006063:Chorionic Gonadotropin; D000509:alpha-Fetoproteins; D004964:Estriol