>>I’m 42 and on my 3rd IVF. I respond well (12+ follicles, near 100% retrieval/fert rates), make beautiful embryos, but they don’t implant. Three REs all say we have “implantation failure”. Specialist say the reason for this is either functional (ie, progesterone surging too early, akin to P27/cyclin E situation) to infectious in nature.
In IVF#1 we put in 6. In IVF#2 we put in another 6. We had 6 frozen embryos, 1 survived thaw and we put in 5. So 17 embryos in three transfers and not a single implantation. We did not do PGD so we opted to always put in more. We went with the assumption that at 41 (my age at retrieval) the odds are that 1 in 5 embryos are normal.<<
From here...
http://infertilityblog.blogspot.com/2006/11/how-many-embryos-are-you-putting-back.html
Then I guarantee you if the clinic that did that was ever found guilty of transferring six, they’d likely lose their accreditation as a fertility clinic.