As Gandalf said to Frodo “Is it safe?” That is certainly an important question to examine. If we pursue PGD we certainly do not want to shoot ourselves in the foot.
First of all, how could PGD create a problem? Well there are several steps that could cause potential problems. The embryo biopsy could result in damage to the remaining cells in the embryo. The removal of 1/8th of the cells in the embryo could alter the development of the embryo. The biopsy of the embryo could result in an embryo that is less tolerant of cryopreservation (freezing). The testing on the embryo could be inconclusive or incorrect. Finally, the assumption that all 8 cells in the embryo are identical and thus representative of the reproductive potential of the entire embryo may be incorrect.
All of these concerns are reasonable and I will address them later but for now let’s see what is in the book...Here is today’s question of the day from the book that all Red Sox fans should buy ASAP: 100 Questions and Answers about Infertility.
73. How safe is PGD or PGS?
An estimated 5,000 cycles of PGD/PGS are being performed in the United States each year. Although the use of these techniques is clearly increasing, the number of PGD/PGS cycles continues to represent only a small fraction of the 100,000 IVF procedures performed annually in the United States alone. The rate of congenital anomalies and of pregnancy complications following PGD/PGS does not appear to be increased over the baseline measurements. On occasion, misdiagnosis may occur, so patients undergoing PGD/PGS are usually offered traditional prenatal diagnostic tests (chorionic villus sampling-CVS or amniocentesis) to confirm the results. The rates of misdiagnosis in PGD range from 1% to 9%. Embryos from which no diagnostic information is obtained are usually discarded rather than risk embryo transfer, although this policy varies from clinic to clinic. The other risks of PGS/PGD are the same as those associated with any cycle of IVF, including multiple pregnancy and OHSS.