October 26, 2009
DENVER, CO– The Colorado Center for Reproductive Medicine (CCRM) announced today a clinical pregnancy success rate of 77% for patients undergoing in vitro fertilization (IVF) with comprehensive chromosome screening (CCS), an ongoing IRB approved clinical study. The IVF pregnancy success rate is about 30% worldwide.
In May of 2007, CCRM began the CCS study, which screens for all 23 pairs of chromosomes in a few cells removed from the embryo on day 5 or 6 of development (blastocyst) using techniques that include comparative genomic hybridization (CGH) and microarray analysis. Chromosomal abnormalities are very common in human embryos, but until now, only a limited number of chromosomes could be analyzed in a blastocyst.
The goal of CCS is to reduce the likelihood of implantation failure, miscarriage and pregnancies affected with chromosomal abnormalities by preferentially transferring only embryos that have the correct number of chromosomes. “There are many variables that contribute to a successful pregnancy,” said William Schoolcraft, MD, Medical Director and Founder of CCRM. “One of them is having an embryo with the correct number of chromosomes. Since a high proportion of failed pregnancies are due to abnormalities in chromosome numbers, CCS helps eliminate one variable from the equation.”
Thus far, a total of 114 patients in the CCS study have had egg retrieval and subsequent frozen blastocyst transfer. Indications for the testing include advanced maternal age, previous IVF failure(s), and a history of multiple miscarriage(s). After the blastocyst embryos are biopsied, they are cryopreserved using a new technique called vitrification, which has resulted in a 97% blastocyst survival rate. The uterus is then prepared for a frozen embryo transfer after the woman’s body is allowed to naturally rid itself of the ovarian stimulation drugs required during an IVF cycle. Eighty-eight of the 114 patients in the study (77%) have ongoing clinical pregnancies, including 41 healthy deliveries to date. The first baby conceived with this procedure was born in June 2008.
“We are thrilled with the outcome of our CCS clinical study,” said Dr. Schoolcraft. “I am also impressed with the ability of thawed embryos to do so well after transfer in cycles unaffected by fertility drugs. With these promising early results, we are continuing the clinical trial, giving patients access to comprehensive chromosome analysis of their embryos with an increased likelihood of pregnancy.”
“Although our older patients are at higher risk to produce aneuploid (chromosomally abnormal) embryos, once we identify euploid (chromosomally normal) blastocysts to transfer, these women have a similar clinical pregnancy rate as our CCS patients who are in their thirties. This is very exciting, as it gives hope for healthy pregnancy to women in their early forties,” says Mandy Katz-Jaffe, PhD, Director of Research at CCRM.
Today, it is common to transfer multiple embryos, which increases the likelihood of implantation but also the chance of multiple births. A single, healthy baby is the optimal goal for both the woman’s health and that of her baby. With an implantation rate (per embryo transferred) of 65%, the CCS study gives potential to make single embryo transfer a successful reality.
About the Colorado Center for Reproductive Medicine
Founded in 1987 by Dr. William Schoolcraft, the CCRM is one of the nation’s leading infertility treatment centers, providing a wide spectrum of infertility treatments ranging from basic infertility care to advanced in vitro fertilization (IVF) technology. Today, joined by Drs. Eric Surrey, Debra Minjarez and Robert Gustofson, Dr. Schoolcraft and his staff achieve some of the highest pregnancy rates in the country. CCRM was ranked “The #1 Fertility Center in the U.S., with the Greatest Chance of Success” by Child.com. For more information visit www.ColoCRM.com
Colorado Center for Reproductive Medicine