Birth defects diagnosis relies on both non-invasive screening methods and invasive diagnostic procedures, depending on the suspected condition and risk factors.
1. Ultrasound
- Ultrasound scans are routinely used during pregnancy to visualize the developing fetus and identify structural abnormalities such as heart defects, neural tube defects, or limb malformations.
- Detailed anomaly scans around 18-22 weeks gestation provide comprehensive assessment of fetal anatomy.
2. Blood Tests (Prenatal Screening)
- Most pregnant women undergo blood tests to assess the risk of chromosomal abnormalities like Down syndrome (trisomy 21) or neural tube defects such as spina bifida.
- These tests measure specific markers in maternal blood and are usually combined with ultrasound markers for more accurate screening.
3. Amniocentesis
- A diagnostic procedure where a small sample of amniotic fluid is collected using a needle inserted into the uterus.
- Amniocentesis provides definitive genetic and chromosomal information to confirm or rule out suspected birth defects.
4. Chorionic Villus Sampling (CVS)
- CVS involves collecting a small sample of placental tissue (chorionic villi) either through the cervix or abdominal wall.
- This test is done earlier than amniocentesis (usually 10-13 weeks) and also allows genetic diagnosis of chromosomal disorders and some birth defects.
Conclusion
Prenatal diagnosis of birth defects is achieved through ultrasound imaging, blood screening tests, and invasive diagnostic procedures such as amniocentesis and chorionic villus sampling. These tools enable early identification of fetal abnormalities, allowing timely counseling and management for expectant parents