The objective of this study is to explore the diagnosis pattern of mid-trimester fetal chromosomal aneuploidy and its clinical applications. A large group of pregnant women (18-34 years) received dual serological screening. The elderly pregnant women, who were at high and critical risk and refused amniocentesis, underwent non-invasive detection of fetal DNA upon recommendation. Then, the pregnant women with positive non-invasive detection results received amniocentesis, amniotic cell culture, and karyotype analysis for confirmation. In total, 24,520 women and 629 elderly women (>35 years) received amniocentesis, amniotic cell culture, and karyotype analysis, and 1512 women received non-invasive detection of fetal DNA. A total of 275 women received invasive prenatal diagnosis. Seventeen cases of trisomy 21, 3 cases of trisomy 18, and 2 cases of sex chromosomal abnormality were diagnosed. The serological screening-gene detection-prenatal diagnosis for mid-trimester fetal chromosomal aneuploidy increased the detection rate, and decreased the frequency of invasive prenatal diagnosis.
Keywords: Chromosomal aneuploidy; Non-invasive detection of DNA; Pattern of prenatal diagnosis.