New first trimester test for Down Syndrome
Posted Nov 10, 2005, 2:39 PM ET by Nicole ApostolaRelated

A first-trimester screening method can more reliably identify fetuses with Down syndrome than the current method, according to a study of more than 38,000 US women. The screening method, which uses a blood test and an ultrasound, can diagnose fetuses at 11 weeks after conception, which would allow mothers to decide whether or not to have follow-up tests to confirm the diagnosis.
Currently, about 5,000 babies are born with Down syndrome each year in the US. Women are usually offered the quadruple test, which would test for Down, at 16 weeks, so the new method would offer a diagnosis five weeks earlier. However, the new method has a false positive rate of 5%, which is only slightly better than the current quadruple test.
Did you have screening tests before your child was born? Would a test like this make you more likely to screen for Down?
Currently, women, especially those at high risk because of their family history or age, are offered a blood test known as the quadruple test about 16 weeks into a pregnancy. Women who test positive can then undergo a procedure called amniocentesis to confirm the diagnosis.
The newer regimen uses an ultrasound test called the nuchal translucency to measure the thickness of the skin on the back of a fetus's neck and a blood test to measure levels of a protein called pregnancy-associated plasma protein A (PAPP-A) and a hormone known as human chorionic gonadotropin (HCG).

Podem ler o artigo completo no link acima mencionado, eu própria ainda não decidi se faço a amniocentese ou 1º o despiste. Trata-se de facto de um tema um tanto ou quando complicado e que cada futura mamã deverá decidir por si.