Noninvasive prenatal testing of fetal aneuploidies by massively parallel sequencing in a prospective Chinese population.

ABSTRACT

OBJECTIVE: The recently developed noninvasive prenatal test (NIPT) presents a new era of prenatal screening. Previously reported studies were primarily conducted on high-risk and advanced maternal age (AMA) pregnancies. We sought to evaluate the performance of NIPT for detection of fetal aneuploidies in a Chinese cohort of women younger than 35 years old in a prospective clinical setting. METHODS: Maternal plasma samples were sequenced to identify the aneuploidies. The results were compared against the serum screening results and validated by karyotyping through invasive procedures and birth follow-up. RESULTS: A total of 1916 prospectively collected maternal plasma samples were sequenced, among which 73 samples (3.8%) failed the sequencing quality control. Birth follow-up missed 111 samples (5.8%). The remaining 1741 samples were analyzed. Sequencing reported 15 aneuploidy samples, including all the T21, T18, and T13 cases. Sequencing performed moderately in identifying sex chromosome aneuploidies, detecting two out of four samples, with a specificity of 99.88% (95% CI 99.53% to 99.98%). CONCLUSIONS: Noninvasive prenatal detection of common fetal aneuploidies is a more sensitive and specific method than triple maternal serum screening. It has a remarkable low false positive rate and is applicable to women younger than 35 years old.