ORLANDO, Fla., Oct. 19, 2011 /PRNewswire/ -- Physicians and scientists from Reproductive Medicine Associates of New Jersey (RMANJ) just released the results of their groundbreaking research study entitled Cleavage Stage Embryo Biopsy Significantly Impairs Embryonic Reproductive Potential While Blastocyst Biopsy Does Not: A Novel Paired Analysis of Cotransferred Biopsied and Non-Biopsied Sibling Embryos. The study, led by Richard T. Scott, M.D. and presented at the American Society of Reproductive Medicine Conference in Orlando, aimed to compare the safety and efficacy of embryo biopsies conducted for the purposes of screening for genetic disease at day 3 (cleavage stage) versus day 5 (blastocyst stage) of embryonic development. The impact that biopsy has on an embryo's ability to implant and develop into a baby has never been studied, until now.
"For twenty years, embryo biopsy for genetic disease screening prior to IVF transfer has been conducted on day 3, known as the cleavage stage, when only 6-8 cells have formed," said Dr. Scott. Day 3 biopsy involves removing 1-2 cells for testing. "Removal of such a proportionately large percentage of the embryo reduces the embryo's chances of implantation."
"More sophisticated techniques now allow biopsy on day 5, the blastocyst stage, when 200 or more cells are present," Dr. Scott continued. "These data demonstrate that day 5 biopsy is much safer. The reason that day 5 biopsy does no apparent harm is that a dramatically smaller portion of the embryo is removed. Another reason is that the sample is taken from the outer layer of the embryo destined to form the placenta, called the trophectoderm (TE)," explained Dr. Scott. "The cells that form the baby are undisturbed, preserving the embryo's true potential."
The study evaluated the impact of embryo biopsy at both days 3 and 5, using two groups. One group received day 3 biopsy and one received day 5 biopsy. For both groups, physicians transferred one biopsied and one non-biopsied embryo into participants. With those that resulted in singleton (one baby) pregnancies, DNA fingerprinting was conducted to determine whether the baby resulted from the biopsied or non-biopsied embryo.
"We found a loss of reproductive potential by more than one third when comparing embryos biopsied on day 3 versus non-biopsied embryos, 31% versus 53%," said Dr. Scott. "These results suggest that day 3 biopsy dramatically decreases an embryo's chances of becoming a healthy baby. In contrast, the implantation rate of biopsied and non-biopsied day 5 embryos was equivalent, 52% versus 54%. This study demonstrated that day 5 blastocyst biopsy is unequivocally safer than day 3 cleavage stage biopsy, and does not diminish the potential for embryos to implant and develop into healthy babies," Dr. Scott explained.
Previous groundbreaking research at RMANJ into its Comprehensive Chromosome Screening technique demonstrated that when chromosomally normal embryos are identified prior to embryo transfer, it increases a couple's chance of conception. "We now know that the safest method is to culture the embryos to the blastocyst stage and biopsy at day 5," Dr. Scott explained. "The chromosomal screening technique we developed is unique in that we can obtain results of genetic analysis in as little as four hours, allowing day 5 biopsy and embryo transfer in one cycle. The combination of culture to day 5, safe embryo biopsy, and utilization of a highly validated and rapid genetic technology dramatically improves delivery rates," said Dr. Scott.
Conducting embryo biopsy on day 5 is much more highly advanced than the day 3 biopsies. "To conduct day 5 blastocyst biopsies with positive results, the embryologists must be skilled and experienced in this method," Dr. Scott continued. "This technology, the only technology of its kind that has been validated through highly advanced and internationally recognized research, is not yet available anywhere else in the world."
Although day 3 biopsies are much more common worldwide, day 3 cleavage stage biopsies are no longer conducted at RMANJ.
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 six locations in NJ. Please call RMANJ at 973-656-2089, or visit www.rmanj.com.
Contact: Tricia Krietzberg
SOURCE Reproductive Medicine Associates of New Jersey