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Prenatal screening for trisomy 21: recent advances and guidelines
1Department of Pathology and Laboratory Medicine, Women and Infants Hospital, Alpert Medical School of Brown University, Providence, RI, USA. jcanick@wihri.org
Clinical Chemistry and Laboratory Medicine
|July 28, 2011
Summary
Prenatal screening for Down syndrome (trisomy 21) has significantly advanced, improving detection rates to 90%–95% with lower false positives. Current strategies offer better identification than older methods like maternal age alone.
Area of Science:
- Medical Genetics
- Prenatal Diagnostics
- Public Health
Background:
- Maternal age was the primary screening method for trisomy 21 in the past.
- Early screening methods had limited detection rates and higher false positives.
- Advances in biochemical and ultrasound markers have revolutionized prenatal screening.
Purpose of the Study:
- To review the historical advancements in prenatal screening for trisomy 21.
- To present current screening strategies and their performance metrics.
- To discuss professional guidelines and US-based screening practices.
Main Methods:
- Review of historical data and literature on prenatal screening for trisomy 21.
- Analysis of performance metrics (detection rate, false positive rate) of various screening strategies.
- Examination of guidelines from professional societies and regulatory bodies.
Main Results:
- Screening performance for trisomy 21 has improved significantly since the 1970s/80s.
- Current strategies achieve 90%–95% detection rates at 2%–5% false positive rates.
- Combined, integrated, and sequential screening strategies represent major advancements.
Conclusions:
- Modern prenatal screening offers substantially improved detection of trisomy 21.
- Current screening protocols provide high accuracy with acceptable false positive rates.
- Guidelines and practices in the USA reflect these advancements in prenatal care.
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