These days, more and more women are waiting until they are well into their 30s (and sometimes even 40s) to begin having children. But many of these women are told that because of their "advanced maternal age," their baby's risk for chromosonal issues are greater, which lead many of them to opt, perhaps unneccessarily, for invasive testing during pregnancy. Today, Parents Ask expert Dr. Jason Rothbart weighs in on this common concern:
Q: I'm 36 years old and 8 weeks pregnant with my first baby. All I keep hearing is that I'm of "advanced maternal age" and have to have invasive testing such as amniocentesis or CVS because my baby is high risk for having Down's Syndrome. I'm nervous. Once and for all, what should I do and what are my options?
A: There are many more pregnant women over 35 today than there were twenty years ago, due to the increased desire of women to postpone childbearing until a career is established, as well as the technological advancements and success rates for in vitro fertilization (IVF) and assisted reproduction. But the "35" age as a cut off for certain tests is becoming antiquated, as all of the screening and diagnostic tests available today are and should be offered to women of every age. The age of 35 was important because that is the age where the risk of Down's Syndrome approximates the risk of miscarriage from an amniocentesis.
With the addition of the non-invasive (ie, no risk to the fetus) first trimester screening test (which takes measurements from an ultrasound and a maternal blood draw to get a risk assessment, eg, 1 in 5,000 chance of Down's), the second trimester screening maternal blood test, as well as chorionic villus sampling (CVS) which retrieves chromosomes from the placenta to be analyzed much earlier in pregnancy than an amniocentesis, the age of 35 is no longer a true cutoff.
This being said, every pregnant woman of any age should have the option to have whichever test will give her and her partner the most peace of mind. It is always appropriate to start with the non-invasive testing (first trimester screen), as this gives a usually very reassuring low risk of any chromosomal abnormalities. Of course, if the results return showing an increased risk of an abnormality, or if a woman simply decides that she wants to know with complete certainty that the chromosome number is normal, she can always get an amniocentesis, which does carry a risk for miscarriage (about 1 in 400), but can give tremendous and vital peace of mind.