Application of QF-PCR Technology Combined With Early Pregnancy Ultrasound in Prenatal Screening for Fetal Chromosomal Aneuploidy.

Context • Abnormalities in the meiosis process after sperm-egg union can cause fetal chromosome aneuploidy. The rate of birth defects and the mortality of fetuses with chromosome aneuploidy is significantly higher than that of fetuses with normal chromosomes. Both ultrasound and quantitative fluorescence polymerase chain reaction (QF-PCR) have limitations when used singly, but their combined use may provide better diagnoses. Objective • The study intended to investigate the value of QF-PCR combined with ultrasound in early pregnancy for prenatal screening for fetal chromosomal aneuploidy, to contribute to the improvement of prenatal examinations, ultimately enhancing the early detection and management of the aneuploidies. Design • The research team performed a retrospective study. Setting • The study took place at the Affiliated Dongguan Hospital at Southern Medical University in Dongguan, China. Participants • Participants were 1082 pregnant women who underwent an ultrasound examination in early pregnancy, 11 weeks to 13 + 6 weeks, at the hospital between January 2019 and January 2022. Outcome Measures • Using the results of participants’ ultrasounds and QF-PCR testing, the research team used the gold standard, a chromosomal karyotype analysis, to evaluate the efficacy in diagnosing fetal chromosomal aneuploidies, of ultrasound alone, QF-PCR testing alone, and their combination. Results • Early-pregnancy ultrasound detected 15 abnormalities, of which seven were an abnormal thickness of the transparent layer of the neck, 22 were abnormal nasal bone, four were a fish-scale appearance of bilateral soles of the feet, and three were other abnormalities, such as an incomplete quadrant of the heart, gastroceles, or dilatation of the pelvis. No cases of missed or failed karyotype cultures occurred. The QF-PCR detected 21 abnormal fetuses, including six with trisomy 21 syndrome, two with trisomy 18 syndrome, one with trisomy 13 syndrome, and 11 with sex-chromosome abnormalities. The sensitivity, specificity, and accuracy of QF-PCR in diagnosing fetal chromosomal aneuploidy were 85.7%, 99.81%, and 99.54%, respectively, and the Kappa value for its consistency with the gold standard was 0.88. The sensitivity, specificity, and accuracy of the ultrasound, combined with QF-PCR in diagnosing fetal chromosomal aneuploidy were 95.23%,99.71%, and 99.63%, respectively, and the Kappa value of combined tests’ consistency with the gold standard was 0.91. Conclusion • QF-PCR combined with ultrasound in early pregnancy can effectively improve the accuracy of prenatal diagnosis of fetal chromosome aneuploidy, especially for high-risk pregnant women with a high, positive, predictive value, providing a feasible detection method for clinical practice. [ABSTRACT FROM AUTHOR]