Parent preferences and prenatal testing for neural tube defects

Area of Science:

• Maternal-fetal medicine
• Medical diagnostics
• Genetics

Background:

• Prenatal screening for neural tube defects (NTDs) typically involves maternal serum alpha-fetoprotein (MSAFP) testing followed by ultrasound or amniocentesis.
• Current strategies often prioritize false-negative risks and amniocentesis-induced fetal loss over false-positive risks and parental preferences.

Purpose of the Study:

• To re-evaluate the cost-benefit analysis of prenatal NTD screening by incorporating false-positive risks and parental preferences.
• To propose an optimized screening protocol that balances diagnostic accuracy with invasiveness.

Main Methods:

• Analysis of risks associated with false-negative and false-positive screening results.
• Inclusion of individual parental preferences regarding potential outcomes (missed abnormality vs. fetal loss).
• Modeling of a tiered screening approach using MSAFP levels and high-resolution ultrasound findings.

Main Results:

• High-resolution ultrasound is recommended for all women with elevated MSAFP.
• Women with moderately elevated MSAFP and negative ultrasound require no further testing.
• Women with highly elevated MSAFP and positive ultrasound also require no further testing.
• Amniocentesis is indicated for women with moderately elevated MSAFP and positive ultrasound, or highly elevated MSAFP and negative ultrasound.

Conclusions:

• Optimizing prenatal NTD screening requires considering false-positive risks and patient values alongside traditional metrics.
• A refined protocol using MSAFP and ultrasound can enhance diagnostic efficiency and reduce unnecessary invasive procedures.
• The precise thresholds for MSAFP require customization based on NTD prevalence and parental preferences.