Genetic Counseling 10-8-10

Today we went to the Baylor College of Medicine to meet with a genetic counselor. She went through the lab results from the D&C and showed us that the baby had 47 chromosomes instead of the 46 that everyone should have. There were 3 copies of chromosome 7. This is an uncommon occurrence that is not passed down genetically in families. You never hear about babies having this abnormality, because it always results in miscarriage. The counselor went through our family histories as well, and did not recommend any further genetic testing or even pre-implantation genetic diagnosis (PGD). She said if we wanted to do some blood tests for peace of mind, that we could test to see if we were carriers for cystic fibrosis (CF) or spinal muscular atrophy (SMA) and get chromosome testing done. I called Dr. Kristiansen's office and got all three added to my blood work for my appointment on Monday. As long as I'm not a carrier of CF or SMA, there is no reason for Brett to be tested. We'll both have the chromosome testing done. Again, she didn't even recommend this, but we figure we might as well. If it turns out that either of us is a carrier, then that will be an easy indicator for us to go ahead and do the PGD.

We were surprised to hear that the counselor did not necessarily recommend PGD because of the possible side effects. We had not really researched it since we had to reason to before, so we didn't realize there were downsides to it. The first aspect of the testing that makes the $5K not really sound worthwhile is the fact that most labs do "fish" testing and only test about 7-10 of the 23 pairs of chromosomes for abnormalities. Chromosome 7 is not one of the ones that gets tested, so PGD would not have prevented this miscarriage. There is a new type of testing called "array" testing which tests all of the chromosome pairs, but since it is new, not all labs do it and even the ones that do don't necessarily do it well. In other words, the results could be that they could only effectively test half of the embryos or something like that. The other downside to PGD is the fact that by removing a small sample of each embryo, it could actually cause the embryos to stop growing or not have as good of a chance at implanting in the uterus. For these reasons (and the fact that the counselor did not recommend it), we will probably skip the PGD on the next round barring any abnormal results from our blood testing.

The last piece of news from the testing...two X chromosomes for the 23rd chromosome pair. It was a girl.