Prenatal Screening for Fetal Syndromes
Prenatal screening procedures are critical aspects of prenatal care because they detect chromosomal anomalies, and metabolic or anatomic structural defects in your developing baby. Advances in medicine allow us to conduct several screening tests for every trimester as conditions present themselves at different points in the growth and development of the fetus. The following prenatal screening procedures are offered:
OSCAR (One-Stop Clinic for Assessment of Fetal Risk) First Trimester Combined ScreeningThe OSCAR Test is an early first trimester test that predicts the risk of 3 chromosomal abnormalities: Down Syndrome(Trisomy 21), Edward’s syndrome (Trisomy 18) and Patau’s syndrome (Trisomy 13). Included in an OSCAR Test is a Nuchal Translucency Test (a measurement where a detailed ultrasound of the baby at 11-14 weeks of gestation is taken and the fluid collection behind its neck is measured). A blood sample from the mother is also taken. These are analysed for levels of PAPP-A (Pregnancy Associated Plasma Protein A) and free beta hCG. The gathered data will show a risk estimate of Down Syndrome with 90% accuracy.
Appropriate Confirmatory TestThe results of these screening tests are not diagnostic as it will only give the numerical risk value which determines if your baby belongs to a low-risk or high-risk group. The tests do not definitely say that your baby has Down Syndrome. This is why appropriate confirmatory tests may have to be done. Confirmatory tests for Down Syndrome include: