Prenatal diagnosis

Question

Hello,

I am the mother of an 8.5 month old baby with cystic fibrosis. My husband and I would like to have other children, but we would like to know more about prenatal screening technique.
We heard about a test developed at the Necker Hospital, which involves analyzing the mother's blood. Is this test available yet? At what stage of pregnancy can it be done?

Thank you in advance

Answer

Dear Madam,
the technique set up by researchers from Necker’s Hospital is based on fetal cells isolation from the maternal bloodstream, making possible their genetic material (DNA) analysis. This method is of great interest because of its non-invasiveness (without threat of fetal abortion) by avoiding fetal cells collection during chorionic villus sampling, amniotic fluid or fetal blood sampling. Some encouraging results have been obtained by those researchers in 12 couples of parents. Nevertheless, the test isn’t routinely used, because some technical issues remain. Isolation of fetal cells in the maternal bloodstream is still puzzling because those cells are mixed with 10 million of white blood cells and 5 billion of red blood cells. Furthermore, the reliability of the test needs to be checked on larger sample sizes. In the article published on this technique in the setting of cystic fibrosis, blood sampling was done between 11 and 13 weeks of gestation.
With my kind regards,
Dr Philippe Reix

15.11.2012