Maternal serum markers in screening for Down syndrome

Area of Science:

• Prenatal diagnostics
• Biochemical markers in pregnancy
• Screening for chromosomal abnormalities

Background:

• Maternal serum screening is crucial for detecting fetal aneuploidies like Down syndrome.
• Current screening methods rely on markers such as maternal serum alfa-fetoprotein and maternal age.
• Improving the accuracy of Down syndrome screening is essential for effective prenatal care.

Purpose of the Study:

• To evaluate the impact of adding estriol and human chorionic gonadotropin (HCG) to existing maternal serum screening markers.
• To assess the combined effect of maternal age and new biochemical markers on Down syndrome detection and false-positive rates.
• To determine the clinical utility of an enhanced screening strategy in antenatal care.

Main Methods:

• Maternal serum samples were analyzed for alfa-fetoprotein, estriol, and HCG levels.
• Maternal age was incorporated as a known risk factor.
• Statistical analysis was performed to compare detection and false-positive rates with and without the new markers.

Main Results:

• The addition of estriol and HCG increased the Down syndrome detection rate from 53.0% to 57.6%.
• The false-positive rate decreased significantly from 9.4% to 7.3% with the enhanced screening.
• The improved accuracy offers more precise risk assessment for pregnant women.

Conclusions:

• A screening strategy combining maternal age with maternal serum alfa-fetoprotein, estriol, and HCG offers improved accuracy for Down syndrome detection.
• This enhanced screening is recommended for incorporation into antenatal care, particularly for women under 35.
• For older women, the refined risk calculation aids in counseling for genetic amniocentesis.