1. First-Trimester Screening (Between 11-14 weeks)
Nuchal Translucency (NT) Scan: This ultrasound scan measures the thickness of fluid buildup at the back of the baby’s neck. Abnormal measurements may indicate an increased risk of chromosomal abnormalities.
Combined First-Trimester Screening Blood Test: This blood test measures specific proteins in the mother’s blood, including pregnancy-associated plasma protein-A (PAPP-A) and human chorionic gonadotropin (hCG). Deviations from normal levels may suggest an increased risk of chromosomal abnormalities such as Down syndrome and trisomy 18.
2. Cell-Free DNA Testing (Between 10-22 weeks)
This non-invasive prenatal test (NIPT) analyzes fetal DNA present in the mother’s bloodstream. It screens for chromosomal abnormalities, such as Down syndrome, trisomy 18, and trisomy 13, with high accuracy. It is usually offered to women at increased risk of having a baby with genetic conditions.
3. Second-Trimester Maternal Serum Screening (Between 15-20 weeks)
Quad Screen (Multiple Marker Screening): This blood test measures the levels of four substances in the mother’s blood
Alpha-fetoprotein (AFP)
Human chorionic gonadotropin (hCG)
Estriol
Inhibin-A
Abnormal levels of these substances may indicate an increased risk of neural tube defects, chromosomal abnormalities, or other genetic conditions.
4. Anomaly Scan (Around 20 weeks)
Also known as the mid-pregnancy ultrasound, this detailed ultrasound scan assesses the baby’s anatomy and development. It checks for structural abnormalities in organs and ensures the baby’s growth is on track.
5. Glucose Challenge Test (Between 24-28 weeks)
This screening test evaluates the mother’s blood sugar levels to assess the risk of gestational diabetes mellitus (GDM). If the initial glucose challenge test result is elevated, further diagnostic testing, such as the oral glucose tolerance test (OGTT), may be recommended.
These are some of the common prenatal screening tests recommended during pregnancy. The timing and necessity of specific tests may vary based on individual factors, including maternal age, medical history, and previous pregnancy outcomes. It’s essential to discuss prenatal screening options with your healthcare provider to determine the most appropriate plan for your pregnancy.
If you have any questions or concerns about prenatal screening tests, don’t hesitate to reach out to your healthcare provider or maternal-fetal medicine specialist for guidance and support.
