Impact of Invasive Prenatal Procedures on Pregnancy Outcomes

Prenatal invasive tests, such as chorionic villus sampling (CVS) and amniocentesis, are frequently performed on women at high risk for having a child with aneuploidy or a genetic disorder. However, data on complications related to these procedures in specific settings is limited.

The aim of a new study was to assess the composite adverse events following invasive prenatal testing.

This prospective, observational study was conducted in the Department of Obstetrics & Gynaecology at the Postgraduate Institute of Medical Education and Research (PGIMER) in Chandigarh, India. The study included 173 pregnant women screened from the antenatal clinic between August 2020 and June 2021 – of whom 150 required invasive testing.

Overall, 32% of the women who underwent invasive testing had CVS, and 68% underwent amniocentesis. The main reason for CVS was hemoglobinopathies (66.7%), while 33.3% had a history of previous babies with genetic defects. For amniocentesis, the primary indication was a positive screen for aneuploidy (58.8%), followed by abnormal findings on an ultrasound anomaly scan. Among the 39 women tested for hemoglobinopathies, 87.1% had a previously affected child, and only 12.8% were identified as beta-thalassemia carriers during prenatal screening. Procedure-related complications, including – miscarriage before 24 weeks, preterm premature rupture of membranes (PPROM), and preterm labor, were observed in 8% of the cases.

The findings indicate that miscarriage risk before 24 weeks after invasive prenatal testing is not significantly higher than in those who do not undergo such procedures. It highlights the importance of strengthening universal prenatal screening for thalassemia carriers––as most cases involved couples with previously affected children.

Source: Thakur V, Bagga R, Sharma B, et al. Indian Obstetrics and Gynaecology. 2024 Jul 23;14(2).