ASRM 2011 Update
ASRM 2011 Updates In addition to the magical wonders of Disney, Orlando welcomed reproductive endocrinologists from around the world this October to attend the annual meeting of The American Society for Reproductive Medicine (ASRM). Several members of Pacific Fertility Center were among the participants.
Preimplantation Genetic Screening (PGS)
PGS was again a hot topic of discussion. Multiple presentations showcased the recent technological advances in this field. The ability to perform comprehensive chromosome analysis using microarray technology instead of the first generation method of FISH (fluorescent in situ hydridization), which could only test a selected number of chromosomes at a time, has increased the accuracy and the detection rate of embryonic aneuploidy (abnormal number of chromosomes). Laboratory advances such as biopsy of the trophectoderm (the outer cell layer of a day 5 embryo) and vitrification (a method of rapid cooling of embryos that minimizes ice crystal formation) have further improved success. As the result of the above-mentioned technical breakthroughs, we have seen a measurable increase in the pregnancy rate and a decrease in the miscarriage rate from IVF using PGS. Additionally, two respected groups independently presented data supporting the use of PGS as a successful embryo selection tool to promote elective single embryo transfer (the process of transferring one embryo at a time into the uterus to reduce the risks of multiple gestation). The pregnancy rates from a single PGS-selected euploid embryo were 58% and 60.7% compared to 42% and 40.7%, respectively, from a morphologically comparable but non-PGS-selected embryo. Moreover, the miscarriage rates decreased to 6% and 6.3% from 12% and 12.5%, respectively. The risk of multiple gestation was essentially eliminated (1-2% monozygotic twining).
We were excited to note the parallels between the data presented and our own work at PFC. Several years ago, we made the commitment towards decreasing our multiple pregnancy rates by adopting a policy of encouraging elective single embryo transfer
Another interesting topic that deserves attention is fertility preservation using oocyte cryopreservation. Two centers with extensive experience in this area shared their outcome data from both methods of cryopreservation, slow freeze and vitrification. A center in Atlanta vitrified over 2000 oocytes from donors with an average age of 26 years. Of the 1772 oocytes rewarmed, 88% survived, 75% fertilized, and 51% resulted in viable cleavage stage (day 3) embryos. Live birth rate per cryopreserved oocyte was 11%. The other presentation by a group in New York reported their experience of rewarming 536 cryopreserved oocytes using both slow freeze and vitrification from non-donors with an average age of 32 years. The overall live birth rate per rewarmed oocyte was 5.5%. Study is ongoing to compare the efficacies of slow freeze and vitrification.
PFCs own data with vitrification of oocytes is comparable to, if not better than, the results presented at our national meeting by various groups across the US. A 5-10% live birth rate per oocyte in women under the age of 35 years translates to a respectable chance of having a baby in the future from one to two treatment cycles in the present (10-20 oocytes can be expected to be cryopreserved per cycle). As we further perfect our own techniques of vitrification, we will be increasingly more confident in our ability to offer young women with a viable option for future family planning in addition to embryo freezing and donor gametes. Future research is needed to achieve the same type of success rates in older women.
Participating at ASRM is always an educational experience. We enjoyed sharing our own clinical and research endeavors with our colleagues across the US and all over the world. Our position as the nations leader in many of the most cutting-edge technologies in our field is a validation of our commitment to excellence and to provide our patients with the highest quality care available.