# Karyotyping with amniotic fluid in 6,572 pregnant women and pregnancy outcomes——A single-center retrospective study

## TL;DR

This study analyzed amniotic fluid karyotypes in over 6,500 high-risk pregnancies to assess chromosomal abnormalities and their impact on pregnancy outcomes.

## Contribution

The study provides empirical data on karyotype detection rates and outcomes in high-risk pregnancies at a single center.

## Key findings

- Abnormal karyotypes were detected in 3.29% of cases, with high-risk noninvasive prenatal testing showing the highest detection rate.
- Numerical chromosomal abnormalities were the main reason for pregnancy termination, accounting for 86.2% of cases.
- The amniotic fluid culture success rate was nearly 100%, indicating high reliability of the diagnostic process.

## Abstract

To detect abnormal chromosome karyotypes in amniotic fluid cells and to explore the relationship among various prenatal diagnostic indications, karyotypes, and pregnancy outcomes.

The data used in this study were obtained from 6,572 pregnant women at high risk for fetal chromosomal abnormalities who visited the Luzhou Prenatal Diagnostic Center for amniocentesis from January 2017 to February 2023. The data were accessed from May to October 2023. Upon admission to the hospital, all pregnant women underwent amniocentesis guided by B-mode ultrasound, followed by karyotyping.

The culture success rate of amniotic fluid was 99.98% (6,571/6,572), with 216 cases of abnormal karyotypes detected (3.29%), including 3 rare cases. There were significant differences in the detection rates of abnormal karyotypes by indication (χ2 = 449.661, P < 0.001), with high-risk noninvasive prenatal testing having the highest rate (36.0%), followed by chromosomal abnormalities in one or both spouses (16.1%). A total of 6,065 cases were followed up (92.3%), and most pregnancy terminations were due to fetal chromosomal abnormalities, specifically numerical abnormalities (86.2%).

All pregnant women with prenatal diagnostic indications should be actively encouraged to undergo prenatal diagnosis and genetic counseling based on their individual circumstances to provide appropriate reproductive guidance, reduce the risk of abnormal births, and promote eugenics.