DENVER, Oct. 21 /PRNewswire/ -- The Colorado Center for Reproductive Medicine (CCRM) announced today its physicians are using an embryo screening technique that allows the infertility clinic to achieve in-vitro fertilization (IVF) success rates for women ages 38 to 42 with chromosomally normal (euploid) embryos that are as good as the rates generally achieved by women 37 years old and under.
"It is as if we are turning back the biological clock for these women," said William Schoolcraft, M.D., the clinic's medical director and founder. "By carefully screening embryos for all 23 pairs of chromosomes, we can determine which have the best chance of implanting and maintaining a pregnancy. This screening results in healthy, viable embryos, reducing the chance of heart-breaking miscarriages and allowing us to transfer a single embryo and avoid the risk of multiple births."
Chromosomal abnormalities are very common in human embryos and often result in miscarriages. As women age closer to 40 years old, the quality of their eggs declines, increasing the chance of chromosomal abnormalities.
In May of 2007, CCRM began the nation's first Comprehensive Chromosomal Screening (CCS) study screening for all 23 pairs of chromosomes in a few cells removed from the embryo on day five of development (blastocyst stage). The CCS techniques used during this study have included comparative genomic hybridization (CGH), microarray and polymerase chain reaction (PCR) based analysis. CCRM is unique in Colorado for being able to offer "in-house" CCS testing allowing for rapid analysis and no transport.
The goal of CCS is to reduce the likelihood of implantation failure, miscarriage and pregnancies affected with chromosomal abnormalities by preferentially transferring only those embryos that have the correct number of chromosomes. "There are many variables that contribute to a successful pregnancy," said Dr. Schoolcraft. "For women near the age of 40, having an embryo with the correct number of chromosomes is a key factor."
Although patients around 40 years old are at higher risk of producing chromosomally-abnormal embryos, once CCRM identifies euploid (chromosomally-normal) blastocysts to transfer, these women have similar ongoing clinical pregnancy rates as patients who are in their thirties. These results suggest that chromosomal abnormalities may play a role in the decrease of fertility with increasing age. There are a percentage of women that will have no normal (euploid) embryos available to transfer. This may also provide further explanation for their underlying infertility.
Thus far, a total of 269 patients in the CCS study have had egg retrieval and subsequent frozen blastocyst transfer. Indications for the testing include advanced maternal age, repeated IVF failure, and/or a history of multiple miscarriages. After the blastocyst embryos are biopsied, they are cryopreserved using a technique called vitrification, which has resulted in a 97 percent 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.
One hundred ninety-seven of the 269 patients in the study (73.2 percent) have ongoing clinical pregnancies, including 172 healthy babies born to date and only eight (4.1 percent) miscarriages. The first fetus conceived with this procedure was born in June 2008. To date, 48 percent of patients receiving CCS are between 38 to 42 years of age; with a 61 percent successful implantation rate for each day five euploid embryo transferred. This figure is generally consistent with the outcome experience of women 37 years and younger. The clinic's results using CCS are being further validated with a randomized control trial led by Mandy Katz-Jaffe, PhD, director of research.
About the Colorado Center for Reproductive Medicine
Founded in 1987 by Dr. William Schoolcraft, 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 on the CCS trial and CCRM, visit www.ColoCRM.com.
SOURCE Colorado Center for Reproductive Medicine