Early amniocentesis is not as safe as second trimester amniocentesis due to increased pregnancy loss and spontaneous miscarriages, and higher occurrences of anomalies, according to a recent Cochrane review. The review included 16 randomized controlled trials and 33,555 women, with very low to high-quality evidence supporting the outcomes studied. Among the findings:
- Early amniocentesis is not as safe as second trimester amniocentesis, demonstrated by increased pregnancy loss and congenital anomalies.
- However, 1 study of 4,606 women found that a second trimester amniocentesis increased spontaneous miscarriages and pregnancy losses.
- Transcervical chorionic villus sampling compared with second trimester amniocentesis may be associated with a higher risk of pregnancy loss.
Alfirevic Z, Navaratnam K, Mujezinovic F. Amniocentesis and chorionic villus sampling for prenatal diagnosis. Cochrane Database of Systematic Reviews. 2017, Issue 9. Art. No.: CD003252. doi:10.1002/14651858.CD003252.pub2.