Prenatal genetic diagnosis is meant to detect chromosomal abnormalities before birth. This knowledge empowers parents to prepare emotionally, physically and financially for a baby with a health problem, and will enable the physicians to perform a timely intervention. Postnatal diagnosis, which is performed after birth, and it helps to verify anomalies detected and assess risk factors.

Useful links:

https://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/in-depth/prenatal-testing/art-20045232