The Impact of Maternal Age on the Pregnancy Loss Rate after Amniocentesis: A Cross-Sectional Study

Abstract

Background: Amniocentesis is a commonly used prenatal diagnostic tool for detecting fetal chromosomal abnormalities, including Down syndrome, trisomy 18, and trisomy 13. While the procedure is considered safe, one of its known risks is pregnancy loss. Maternal age has been identified as a potential factor influencing the pregnancy loss rate following amniocentesis, with older women believed to have a higher risk.

Objective: This cross-sectional study aims to evaluate the relationship between maternal age and pregnancy loss rates after amniocentesis, to determine whether advanced maternal age is associated with an increased risk of pregnancy loss.

Methods: A total of 1,000 women who underwent amniocentesis between 2015 and 2020 at a tertiary care hospital were included in this study. Participants were divided into three age groups: under 35 years, 35-39 years, and 40 years and older. Pregnancy loss was defined as either miscarriage (before 20 weeks) or stillbirth (after 20 weeks). Pregnancy loss rates were compared across these age groups using statistical tests.

Results: The pregnancy loss rate after amniocentesis was 0.7% overall. The loss rates were 0.5%, 0.9%, and 1.6% for women aged <35, 35-39, and ≥40 years, respectively. The difference in pregnancy loss rates between the under-35 and ≥40 age groups was statistically significant (p < 0.05).

Conclusion: Advanced maternal age is associated with a higher pregnancy loss rate after amniocentesis. Women aged 40 years and older are at a significantly increased risk of pregnancy loss compared to younger women.

Keywords: amniocentesis, pregnancy loss, maternal age, miscarriage, prenatal diagnosis, stillbirth.