Related Experiment Videos
Advances in prenatal screening for Down syndrome: I. general principles and second trimester testing
1Division of Human Genetics, Department of Pediatrics, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, CT 06030-6140, USA. benn@nsol.uchc.edu
Summary
Second trimester screening helps identify pregnancies at higher risk for Down syndrome. Current methods like triple and quadruple testing serve as benchmarks for improving prenatal screening efficacy.
Area of Science:
- Prenatal screening and diagnosis
- Maternal serum screening
Background:
- Down syndrome is a leading cause of mental retardation, with a birth prevalence exceeding 1:600 without prenatal screening.
- Prenatal screening aims to identify high-risk pregnancies and offer women more options.
Purpose of the Study:
- To evaluate second trimester serum screening methods for Down syndrome.
- To establish benchmarks for new screening protocol development.
Main Methods:
- Second trimester serum screening combines maternal age-risk with analyte concentrations: maternal serum alpha-fetoprotein (MSAFP), unconjugated estriol (uE3), and human chorionic gonadotropin (hCG) (triple testing).
- Quadruple testing incorporates inhibin-A (INH-A) alongside triple test analytes.
- Accurate gestational age assessment is crucial for optimal screening. Fetal biometry via ultrasound may refine Down syndrome risk estimates.
Main Results:
- Triple and quadruple tests identify Down syndrome, trisomy 18, Turner syndrome, triploidy, and other conditions.
- These tests serve as benchmarks for assessing novel screening protocols.
Conclusions:
- Second trimester triple and quadruple tests are valuable benchmarks for evaluating new screening protocols.
- Integrating fetal biometry and developing new tests, alongside clarifying co-factor roles in analyte concentrations, will enhance second trimester Down syndrome screening efficacy.