Frozen embryo transfers have been an integral part of our IVF practice for decades at Texas Fertility Center, and the new research in Fertility and Sterility confirms our initial research, as well as our shift to frozen embryo transfer protocols
Austin, TX (PRWEB) October 11, 2017
A new study published in Fertility and Sterility in August compared the implantation and pregnancy rates in frozen and fresh in vitro fertilization (IVF) transfer cycles. The multi-center matched cohort study examined the contribution of progesterone and maternal age to IVF success.
After comparing the results from the fresh and frozen transfer cohorts, the authors of the study determined that freeze-only transfer protocols produce statistically significantly higher implantation and pregnancy rates compared with fresh cycles, especially when the woman has a progesterone level >1.0 ng/mL at trigger. The results remained consistent for women both above and below age 35.
The study has lead researchers to conclude that fertility specialists should shift their embryo transfer protocols from fresh to frozen, confirming the results of research that Texas Fertility Center published two decades ago.
The first to prove the link between progesterone production, FET and IVF success
In 1991, Kaylen Silverberg, M.D., the medical director of Texas Fertility Center, and other experts in the field evaluated the effect of premature progesterone production on pregnancy rates in IVF cycles. They concluded that even minimally increased progesterone production prior to ovulation trigger significantly lowered pregnancy rates. These findings were confirmed by several other studies, however, unlike Silverberg and his colleagues, those authors suggested that progesterone adversely affected the eggs or embryos. In contrast, Silverberg hypothesized that progesterone caused the uterine lining to prematurely mature, while leaving the eggs and embryos unaffected. “We thought that high progesterone levels had a negative effect on the uterine lining, not the eggs and embryos,” said Dr. Silverberg.
To determine a definitive answer, he and his colleagues then performed a study looking specifically at embryos that were frozen rather than transferred fresh. When they compared pregnancy rates, they found that embryos frozen from cycles with elevated progesterone levels provided the same chance for pregnancy as embryos frozen from cycles with lower progesterone levels. This confirmed their belief that progesterone affected the uterine lining rather than the egg or the embryo. The results of the study, published in 1994, were groundbreaking – rather than canceling IVF cycles due to premature progesterone production, fertility specialists learned they could simply freeze all of a patient’s embryos for transfer during a later cycle. The reproductive endocrinologists at Texas Fertility Center continued these studies and began performing only frozen embryo transfers several years ago.
Freezing embryos allows fertility specialists to transfer embryos into a woman’s uterus once progesterone levels have dropped and the uterine lining has returned to an optimal condition for implantation.
Research supports protocols for FET
“The team at Texas Fertility Center is known for performing leading-edge research and incorporating these findings into everyday practice for our patients. Frozen embryo transfers have been an integral part of our IVF practice for decades at Texas Fertility Center, and the new research in Fertility and Sterility confirms our initial research, as well as our shift to frozen embryo transfer protocols,” said Dr. Silverberg.
About Dr. Kaylen Silverberg
Dr. Silverberg has served two terms on the board of directors for the Society for Assisted Reproductive Technologies (SART). Dr. Silverberg has also been honored by the American Fertility Association with their national Family Building Award, and is recognized annually as a Best Doctor in America™. Actively involved in infertility research for more than two decades, Dr. Silverberg has published his findings extensively in infertility journals and textbooks of infertility and gynecology. He is a founder of Ovation Fertility™ and Ovation Fertility™ Genetics, national leaders in IVF and pre-implantation genetic embryo testing. Dr. Silverberg is board-certified in obstetrics and gynecology as well as reproductive endocrinology/infertility.
For more information, please visit http://www.txfertility.com.