Role of ultrasound for Down syndrome screening in advanced maternal age

• Published in: American journal of obstetrics and gynecology 2001-11, Vol.185 (5), p.1028-1031
• Main Authors: Egan, James F.X., Malakh, Lillian, Turner, Garry W., Markenson, Glenn, Wax, Joseph R., Benn, Peter A.
• Format: Article
• Language: English
• Subjects: Adult; Aging - blood; Biological and medical sciences; Diseases of mother, fetus and pregnancy; Down Syndrome - diagnosis; Down Syndrome - diagnostic imaging; Down Syndrome - genetics; Down syndrome screening; False Positive Reactions; Female; genetic sonogram; Gynecology. Andrology. Obstetrics; Humans; Mass Screening - methods; Maternal Age; Medical sciences; Middle Aged; Pregnancy; Pregnancy, High-Risk; Pregnancy. Fetus. Placenta; Retrospective Studies; Sensitivity and Specificity; Ultrasonography, Prenatal
• ISSN: 0002-9378; 1097-6868
• DOI: 10.1067/mob.[phone]

Objective: To determine the sensitivity and false-positive rate of Down syndrome screening by use of maternal serum screen and the genetic sonogram in women ≥35 years of age. Study Design: We searched our perinatal databases retrospectively from January 1992 to January 2000 for the following criteria: known Down syndrome fetus or newborn, advanced maternal age, and genetic sonogram from 14-24 weeks’ gestation. The a priori maternal age or maternal serum screen risk was modified by likelihood ratios for ultrasound markers. Without markers the risk was reduced by 50%. The cut-off was 1:270. Results: Age and maternal serum screen had a sensitivity of 90.5% and a false-positive rate of 27.1%. Age and ultrasound had a 95.2% sensitivity and 43.5% false-positive rate, whereas the combination of age, maternal serum screen, and ultrasound had a 97.6% sensitivity and a 22.0% false-positive rate. Conclusion: The combination of age, maternal serum screen, and ultrasound improves the sensitivity for Down syndrome detection in the advanced maternal age population. (Am J Obstet Gynecol 2001;185:·1028-31.)