Impact of a Predetermined Day 5 Embryo Transfer Versus a Predetermined Day 6 Embryo Transfer on the Clinical Pregnancy Rate After Intracytoplasmic Sperm Injection (ICSI) Treatment

Since a predetermined embryo transfer on day 5 cannot be performed in some centers on every day of the week (e.g. sunday), some IVF centers perform a predetermined embryo transfer on day 4 or day 6, respepectively. Data for a predetermined embryo transfer on day 4 versus a predetermined embryo transfer on day 5 showed no significant differences regarding clinical pregnancy rates. However, since a day 6 transfer might offer advantages in assessing the development stage, the prolonged culture and transfer on day 6 transfer might be a very promising option.

As of yet, there are no prospective studies in the current literature examining the equivalence of a predetermined embryo transfer on day 6 versus a predetermined embryo transfer on day 5.

The aim of this prospective multicenter study is to investigate the influence of a predetermined embryo transfer on day 6 compared to a predetermined embryo transfer on day 5. The study population consists of the control group (predetermined embryo transfer on day 5) and the study group (predetermined embryo transfer on day 6). The primary endpoint is the clinical pregnancy rate (detection of a gestational sac) per embryo transfer and the secondary endpoint is the abortion rate per clinical pregnancy. The data from the multicenter study are obtained at three test centers (Fertility Center Dortmund, Fertility Center Essen and Fertility Center Bad Münder).