Invasive procedures, amniocentesis and villocentesis (CVS) allow the diagnosis of chromosomal abnormalities, but these invasive procedures are associated with a risk of miscarriage or other complications. See amniocentesis and CVS risks. For almost 30 years maternal age has been the main reason for women to have an invasive test, but in recent years new more accurate methods than maternal age alone to detect pregnancy at increased risk of chromosomal abnormalities have been developed. There is a screening programme by the National Health System since 2007 is available. The aim of the screening is to identify those women at higher risk of having a baby with Down’s Syndrome and offer them diagnostic testing. The challenge of an antenatal screening programme is to identify women in whom a risk of Down’s Syndrome is sufficiently high to justify such an invasive test and to minimise the risk of miscarrying a healthy baby.
FAQs (Frequently asked questions)
	Q. I am 36 years old and because of my age I have been advised to have an invasive test “to be on the safe side”..but this carries a risk!
A. NT is three times more reliable compared to age to decide if to have an invasive test. Even at 40 years old a woman may be reclassified “low risk” if biochemical and fetal parameters are within normal range.
	Q. I am 26 years old, I feel fine and I have no history of chromosomal problems in my family or in my husband’s family. What is the advantage for me of having the test being already “low risk”?
A. “Low risk” doesn’ t mean “No risk”. Having a pregnancy with a chromosomal problem may happen at any age. The vast majority of babies with chromosomal defects are born in women that have less than 35 years. (read more). Nuchal translucency detects the majority of these pregnancies “at risk”.