"When Amy Seitz got pregnant with her second child last year she knew that being  years old meant there was an increased chance of chromosomal disorders like Down syndrome. She wanted to be screened and she knew just what kind of screening she wanted  a test thats so new some women and doctors dont quite realize what theyve signed up for. This kind of test  called cell free fetal DNA testing http uses a simple blood sample from an expectant mother to analyze bits of fetal DNA that have leaked into her bloodstream. Its only been on the market since October  and is not regulated by the Food and Drug Administration  the FDA does not regulate this type of genetic testing service. Several companies now offer the test including Sequenom httpslaboratories.sequenom.compatientsmaternitplus and Illumina http Insurance coverage varies and doctors often only offer this testing to women at higher risk because of things like advanced maternal age. I think that I initially heard about it through family and friends says Seitz. They had had the option of it given to them by their doctors. Article continues after this message from our sponsor To her it sounded great. She didnt want an invasive procedure like amniocentesis  http chorionic villus sampling http are considered the gold standard for prenatal genetic testing but doctors must put a needle into the womb to collect cells that contain fetal DNA which means a small risk of miscarriage. Peter GardinerScience Source  http I wasnt interested in going as far as getting an amniocentesis because of the risk associated with that she explains and so when I heard about this test that was part of the reason that I was most interested in it. This new way of testing fetal DNA seemed to have already become fairly common where Seitz used to live in Washington D.C. But she had recently moved to Alabama and the clinic she went to there wasnt as familiar with it  although when she talked to her doctor she learned the clinic had just had a visit from a companys sales representative. I think it was a fairly new test for them at that point but she was interested in pursuing it further to see what needed to be done Seitz says. Seitz got her blood drawn last July becoming one of hundreds of thousands of pregnant women whove opted for this new kind of test instead of the more traditional invasive ones. Doctors say the impact has been huge. Those of us in the field who do diagnostic procedures like CVS and amnio have seen a drastic decrease in the number of those procedures that are being performed says Dr. Mary Norton httpobgyn.ucsf.edumfmnorton.aspx an expert on maternalfetal medicine and genetics at the University of California San Francisco. Places are reporting doing fewer than half the number of procedures that were being done previously. But she says things have changed so quickly that it may be hard for doctors and patients to know what theyre dealing with. Its still new and its quite different than previous genetic testing thats been available says Norton. Its quite a different paradigm if you will. An invasive test like amniocentesis or CVS lets doctors get a complete picture of the chromosomes and a solid diagnosis. Until the new testing technology came along the only less invasive option was for an expectant mother to get an ultrasound http plus have her blood tested for specific proteins. This can reveal if theres an increased risk of certain disorders but its not very accurate and produces a lot of false alarms. Studies http have shown that the new fetal DNA tests do a better job says Norton. Theyre less likely to flag a normal pregnancy as high risk. Theyre much more accurate than current screening tests but they are not diagnostic tests in the sense that amniocentesis is says Norton and so I think that has led to some confusion. Even though the newer blood tests do look at fetal DNA they cant give a definitive answer like an amniocentesis can because theyre analyzing scraps of fetal DNA in the mothers blood that are all mixed up with her own DNA. Norton says when women get worrisome results from one of these new tests and are referred to her center they sometimes dont understand why doctors are offering a followup amnio because they were under the impression that this was as good as an amnio. She is concerned that some people might end a pregnancy without getting confirmatory testing and points to one study http last year that found a small number of women did that. Theres at least some evidence that its happening to a greater degree than I think many of us are comfortable with she says. The tests are being used more and more widely. Some worry that the companies websites and marketing materials dont make the limitations clear enough. But Dr. Lee Shulman httpsfsmweb.northwestern.edufacultyfacultyprofile.cfmxid doesnt see it that way. Hes an obstetrician and geneticist at Northwestern University in Chicago who has consulted for a couple of the testing firms. Patients need to understand that while this is better it is not a diagnostic test and I think the companies have done a great job in putting this material out he says. Whether or not clinicians use this material and take it to heart and use it for patient counseling is a different story. He says the technology is so new that a lot of doctors have no experience with it and consumers need to understand that. If the patient if the couple are not getting the answers not getting the information they feel comfortable with they need to seek out prenatal diagnostic centers maternal fetal specialists clinical geneticists who may have more experience says Shulman. For example heres one thing that might turn out to be a little more complicated than wouldbe parents might expect. Along with screening for the common chromosomal disorders companies offer parents the chance to learn their babys sex  weeks before its clear on a sonogram. Many women are very excited by the idea that as part of their blood testing they could find out pretty definitively if the baby is a boy or a girl says Dr. Diana Bianchi https an expert on prenatal diagnostics at Tufts University School of Medicine. What they may not realize she says is that the test will also determine whether theres something abnormal about the sex chromosomes. Approximately  in  pregnancies theres an extra X or extra Y she says noting that these are mild conditions that would normally go undetected unless a woman had an invasive test like an amnio. Some babies with these conditions grow up into adulthood and never know they have them unless they face a symptom like infertility. Seitz in Alabama thought it was a bonus that getting this new blood test would tell her if she was having a boy or a girl. But it actually didnt do that because of a paperwork glitch. The box for sex got unchecked somewhere along the way so we werent able to find it out from the test says Seitz who learned from an ultrasound that she was having a girl. The results she did get from the fetal DNA test were reassuring."