Nuchal folds test is an ultrasound prenatal screening test conducted to help identify a higher risk of Down syndrome in developing babies. The test may be recommended for older mothers-to-be who have higher risks of such pregnancies. This test is conducted between weeks 11 and 13.
During the scan, a technician assesses the amount of fluid behind the neck of the baby (also known as "the nuchal translucency"). Babies at risk of Down syndrome tend to have a higher amount of fluid around the neck.