Many times women are concerned after experiencing failed IVF with a fresh embryo transfer if it is best to move right along into another cycle for a frozen embryo transfer. They wonder if there are any carryover effects from the ovarian stimulation and if they should wait to cycle to minimize any residual effects that could potentially impact endometrial receptivity. So, the question is, “Will waiting before performing my frozen embryo transfer cycle increase my chances to become pregnant?”
Recently a group of researchers in Belgium (Santos-Ribeiro, et al.) analyzed data from women who had at least one frozen embryo transfer after ovarian stimulation for IVF from January 2010 to November 2014; totaling to 1,087 women with 1,183 frozen embryo transfer cycles. They divided their samples according to time intervals from egg retrieval to the frozen embryo transfer cycle start date. The frozen embryo transfer start date was either immediate (≤ 22 days after egg retrieval) or delayed (>22 days after egg retrieval).
They determined there is no significant different in clinical pregnancy rates if the frozen embryo transfer is performed immediately or is delayed. Even after adjusting for potential confounding factors such as age, number of good-quality embryos produced, type of frozen embryo transfer cycle, stage and number of embryos transferred, and quality of embryos transferred, there was still no significant difference. In a numbers perspective, the live birth rate after immediate frozen embryo transfer was 24.4% versus 24.1% after delayed frozen embryo transfer. After looking into potential confounding factors the predicted probability for live birth rate of an immediate frozen embryo transfer is 24.5% versus 24.1% delayed frozen embryo transfer.
Even though a majority of patients delay their frozen embryo transfer cycle due to patient stress, treatment discontinuation, or numerous clinically unrelated reasons; this article shows there is no need to wait for a frozen embryo transfer cycle. They did not find that ovarian stimulation had any carryover effect on the clinical pregnancy rate. Therefore, patients have the option to have a frozen embryo transfer cycle immediately or delayed. If it is delayed, it only delays the time to pregnancy.
At InVia Fertility Specialists, we have a very successful frozen embryo transfer program. Currently, our pregnancy rates in young patients with the transfer of a single chromosomally normal embryo (SMART IVF) is around 70%!
Kelly Schorsch is one of the members of the Embryology team at InVia Fertility. She works in both the Andrology and Embryology sections. She completed her graduate studies at Eastern Virginia Medical School in Clinical Embryology and Andrology and her undergraduate studies at Roosevelt University with a major in Biology, minor in Chemistry, and certificate in Biotechnology. She loves to be behind the scenes in the laboratory to help couples achieve their dreams of one day having a baby.