This test, which entails measuring the baby and evaluating it with ultrasound, may be performed when your pregnancy is between 11 and 13.5 weeks gestation (13 weeks is the ideal period). Together with the mother’s age and the outcomes of the related blood test, these are input into software created by the Foetal Medicine Foundation. We may then use this algorithm to determine each pregnancy’s unique risk of chromosomal abnormalities.
It is a risk assessment exam. Which pregnancies are impacted by chromosomal abnormalities is not disclosed by it. Just as low risk does not completely rule out an anomaly, about 5% of pregnancies will return as high risk, with the majority of them being normal.
Between 88 and 93 percent of impacted pregnancies will be identified by this screening technique.
