Ever since we got our Trisomy 18 diagnosis in our first IVF pregnancy, I have been obsessed with the idea of doing PGD (preimplantation genetic diagnosis) so that we could make sure we only put back the embryos with the correct number of chromosomes. My RE (reproductive endocrinologist) was not so hot on the practice. She took our loss very personally I think and spoke with some very well-respected embryologists, including the one at her own practice.
As she explained it to us, their had been no research on the effect of PGD on the embryo itself (i.e. are they less viable once a cell is removed for testing?), and also they were only something like 90 to 95 percent accurate due to differences in how early embryos develop (sometimes not all the cells are adversely affected by the defect and the embryo can essentially grow out of it as the healthy cells outnumber the unhealthy ones.) This is the gist of it. I am not a scientist, and it was a little while ago that we last discussed it. But due to its low accuracy rate, the RE explained that it was not considered to be a replacement for amnio or CVS in diagnosing chromosome problems.
On the other hand, at the perinatologist practice that did our amnio and termination, the nurse midwife practitioner who assisted with my case was very passionate about the need for PGD and how she saw more IVF patients for terminations due to chromosome defects than she saw "naturally" pregnant women for terminations due to chromosome defects. She was horrified that PGDs were not routinely offered to IVF patients.
I was horrified at my experience with her and with my termination. Some day I will write about it, but it's hard to even think about.
When told about the nurse's opinion which she had formed based not on any scientific research but instead on her own anecdotal experience, my RE phoned the peri's office to complain about her. I don't know what ever happened with that.
But anyway, given my experience and obsession with the topic of whether PGD is good or not, it was with great interest that I clicked through to read this story today: Researchers question use of fertility practice about the use of PGD to screen for chromosome problems in the fetuses of older women.
The article said that pregnancy rates were lower in women who had PGD performed during their IVF cycles.
But this article is not as good as the one in the NYT today: Embryo sifting fares poorly in one study. This article mentions the fact that some of the embryos that were biopsied had the procedure performed when they were only at 4 cells, not the recommended 8-cell stage, which could hurt the chances of survival for th embryo.
These articles mentioned that the study said PGD screening for carriers of genetic diseases was still considered valid.
Important to note, however, that the NYT article mentioned that not all doctors agreed with the findings of the study in terms of using PGD to diagnose problems in the embryos of older women. Some believed that the study was flawed.
Another study presented at that same conference was about how herbal medicine supposedly reduced the chances of IVF success. Here's a press release about it. This study seems to lump together a whole bunch of stuff -- nutritional supplements, herbal medicine, acupuncture, etc. and determines that overall they hurt the chances of IVF success.
The study does not, however, address why women turned to such therapies (are they more stressed out to begin with? Have they already undergone many ART procedures without success?)
Also, it doesn't break out the various therapies. So acupuncture is lumped in with nutritional supplements. It doesn't break out various acupuncture techniques (i.e. did the practitioner use the protocols of the swiss or german studies?) It doesn't break out the different types of nutritional supplements (i.e. are these women taking Fertility blend for women? or are they taking more folic acid? or are they taking something else. How can you lump all these things together and put them under a single category?)
(Needless to say, I think this study does a poor job of telling us anything real about the impact of alternative therapies on IVF outcomes. Even non-scientist me can pick it apart.)
