Comparative Screening Performance of Noninvasive Prenatal Testing in Assisted Reproduction and Spontaneous Pregnancies.

Objective

To compare noninvasive prenatal testing (NIPT) performance between pregnancies conceived with assisted reproductive technology (ART) and spontaneously conceived pregnancies, and explore NIPT application characteristics in the ART population.

Method

A single-center retrospective study enrolled 193,376 pregnancies undergoing NIPT, divided into assisted conception (n = 7021) and spontaneous conception (n = 186,355) groups. Prenatal diagnosis for positive results and follow-up were conducted. Participant profiles, positive rates, prenatal diagnosis rates and positive predictive values (PPVs) were compared for the two groups.

Results

The assisted conception group had a higher maternal age (32.12 ± 4.79 years), twin pregnancy rate (13.63%), NIPT failure rate (0.60%), and lower fetal cell-free DNA fraction (13.11 ± 6.76%). The overall NIPT-positive rate (1.82%) did not differ between spontaneously conceived pregnancies after adjusting for twin and maternal age (p = 0.078). No differences in common trisomy-positive rate, prenatal diagnosis rate, PPVs, or termination of pregnancy were observed between the two groups. The PPVs of NIPT for sex chromosome aneuploidies (SCAs), rare autosomal aneuploidies (RAAs), and copy number variants (CNVs) were also not significant between the two groups.

Conclusion

NIPT performs comparably for common trisomies, SCAs and CNVs in ART-conceived and spontaneously conceived pregnancies. But ART pregnancies have higher NIPT failure rates and distinct positive result profiles, requiring targeted genetic counseling.