BASKING RIDGE, N.J., Sept. 12, 2012 /PRNewswire/ -- A new study conducted by Reproductive Medicine Associates of New Jersey (http://www.rmanj.com) has shown that transferable embryos after oocyte vitrification (egg freezing) have similar chances of culminating in pregnancy as those derived from fresh oocytes without increasing the risk of aneuploidy (abnormal number of chromosomes). The findings appear in the September 2012 issue of Fertility & Sterility (Volume 98, Issue 3).
"This study provides an important piece of safety data that had been missing from the egg freezing story, namely that the embryos produced after vitrification are not at an increased risk of being chromosomally abnormal and are just as likely to implant and deliver healthy newborns," said Eric J. Forman, M.D., and lead investigator. "Women who have to delay reproduction for a variety of reasons -- including prior to chemotherapy for cancer -- can for the first time do so with security, knowing that the embryos that develop later are just as likely to be normal. With very high implantation rates, you don't need to transfer more embryos. These women can take advantage of all the benefits of single blastocyst transfer even if they are at an advanced reproductive age when they are ready to use the frozen oocytes."
"This study was the first well-controlled clinical trial of the impact of oocyte vitrification on embryo development and clinical outcome," said Richard T. Scott, Jr., M.D., F.A.C.O.G., H.C.L.D., founding partner of RMANJ. "I congratulate lead investigator, Dr. Eric Forman and his collaborators on this outstanding research and contribution to Reproductive Endocrinology. The implications for fertility preservation, oocyte donation, and possibly routine fertility care are enormous."
In an accompanying editorial, Ana Cobo, Ph.D., a leader in oocyte vitrification in Europe, concluded that with this study, a "Watershed in ART" has been reached, opening a new window of hope for the growing population of female cancer survivors and for women whose career choices challenge their biological clocks. In the editorial Dr. Cobo emphasized the power and value of this landmark study: The evidence that aneuploidy is not increased in vitrified oocytes is a welcome endorsement of the safety of the vitrification technique and constitutes a giant step toward its definitive validation as a strategy for fertility treatment.
About the Study
The paired, randomized controlled trial was designed to assess the impact of oocyte vitrification on aneuploidy and reproductive potential by comparing vitrified and control oocytes from a single patient within a single cycle and a single fresh transfer. The study included forty-four patients with a mean age of 29.9 +/- 2.3 years and normal ovarian reserve.
The primary outcome measure was the rate of aneuploidy. Additional outcome measures included: fertilization, cleavage, blastulation, and implantation in embryos derived from vitrified and control oocytes.
A total of 588 mature oocytes were randomized, with 240/294 (81.6%) surviving vitrification. Among surviving vitrified oocytes, there was no difference in the rate of embryonic aneuploidy (vitrified, 29.1% vs. control, 26.4%). In paired blastocyst transfers, the ongoing pregnancy rate per embryo was comparable (vitrified, 53.9% vs. control, 57.7%). There were differences noted in embryonic development. There was a lower fertilization rate with intracytoplasmic sperm injection (77.9% vs. 90.5%), a lower cleavage rate (90.9% vs. 99.2%), and a lower usable blastocyst formation rate per two pronuclei (34.8% vs. 50.8%).1 The authors noted that while there were differences, the rates achieved with vitrified oocytes were excellent compared with published rates from other centers using fresh oocytes.
About Reproductive Medicine Associates of New Jersey
Reproductive Medicine Associates of New Jersey have pioneered and successfully implemented a cutting-edge technology, known as Comprehensive Chromosome Screening (CCS) to more accurately detect healthy embryos that will lead to successful pregnancies and ultimately healthy babies. Other centers have attempted similar testing methods, but RMANJ is the only fertility center in the world to have developed a system of unprecedented accuracy, fully validated through years of rigorous clinical research. RMANJ's Comprehensive Chromosome Screening offers advanced embryo selection with extreme accuracy by detecting and avoiding use of embryos with chromosomal abnormalities prior to transfer and pregnancy.
The fertility experts at RMANJ have among the highest IVF success rates in the country. Since 1999, they have helped bring more than 20,000 babies to loving families. In addition to serving as the Division of Reproductive Endocrinology at Robert Wood Johnson University Medical School in New Brunswick, NJ, the practice has seven locations in New Jersey. For more information please call RMANJ at 973-656-2089, or visit www.rmanj.com.
1. Forman EJ, Li X, Ferry KM, Scott K, Treff N, Scott RT Jr. Oocyte vitrification does not increase the risk of embryonic aneuploidy or diminish the implantation potential of blastocysts created after intracytoplasmic sperm injection: a novel, paired randomized controlled trial using DNA fingerprinting. FertilSteril 2012;98:644-49.
SOURCE Reproductive Medicine Associates of New Jersey