ĐẶC ĐIỂM DI TRUYỀN VÀ KẾT CỤC THAI KỲ Ở CÁC TRƯỜNG HỢP CÓ NIPT NGUY CƠ CAO VỚI LỆCH BỘI KHÁC T13, T18 VÀ T21 TẠI BỆNH VIỆN ĐẠI HỌC Y DƯỢC THÀNH PHỐ HỒ CHÍ MINH

Abstract

NIPT) has been increasingly applied in obstetric practice due to its high sensitivity and specificity for detecting common aneuploidies (trisomy 13, 18, and 21). However, evidence regarding its predictive value and pregnancy outcomes for rare autosomal aneuploidies (RAAs) and sex chromosome aneuploidies (SCAs) remains limited, particularly in Vietnam. Describing genetic characteristics and pregnancy outcomes in this group is essential to support genetic counseling and clinical management. Objective: To describe the genetic characteristics and pregnancy outcomes in cases with high-risk NIPT results for aneuploidies other than trisomy 13, 18, and 21 at the University Medical Center, Ho Chi Minh City. Methods: A retrospective case series study was conducted on 44 pregnant women with high-risk NIPT results for non-T13/18/21 aneuploidies, who received counseling and/or follow-up at the Prenatal Diagnosis Unit, University Medical Center, Ho Chi Minh City, from July 2021 to June 2024. Data collected included sociodemographic characteristics, clinical history, invasive diagnostic results (amniocentesis, chorionic villus sampling), postnatal karyotype, ultrasound findings, and pregnancy outcomes. After delivery, developmental screening of children was performed using the Ten Questions Screening Instrument (TQSI). Results: Among 44 eligible cases, 25 women (56.8%) underwent invasive testing (24 amniocenteses, 1 chorionic villus sampling). Chromosomal abnormalities were confirmed in 12 cases (48.0%), while 13 cases (52.0%) showed normal karyotypes. The detection rate of chromosomal abnormalities was 42.9% in RAAs and 55.6% in SCAs. Regarding pregnancy outcomes, 77.3% continued to live birth, 6.8% resulted in stillbirth or termination, and 15.9% were lost to follow-up. A total of 34 liveborn children were evaluated postnatally, of whom 8.8% were identified with neurodevelopmental abnormalities using TQSI. Conclusions: High-risk NIPT results for rare aneuploidies present significant challenges in prenatal counseling and management due to the limited concordance with invasive diagnostic testing. This study contributes practical evidence from Vietnam on the genetic features and pregnancy outcomes of pregnancies with high-risk NIPT for RAAs and SCAs, highlighting the importance of confirmatory invasive testing and long-term developmental follow-up.