Cumulative newborn rates increase with the total number of transferred embryos according to an analysis of 15,792 ovum donation cycles
Cumulative newborn rates per total number of embryos needed to achieve a newborn provide an accurate idea of the likelihood of success in consecutive ovum donation cycles.
Nicolás Garrido, Ph.D., M.Sc., José Bellver, M.D., José Remohí, M.D., Pilar Alamá, M.D., Antonio Pellicer, M.D.
Volume 98, Issue 2 , Pages 341-346.e2, August 2012
To measure the success of in vitro fertilization (IVF) of donated ova according to cumulative newborn rates (CNBR) per number of embryos required to achieve at least one newborn (EmbR), considering in addition the relevance of age and infertility etiology.
Survival curves and Kaplan-Meier methods were employed to analyze CNBR with respect to the number of EmbR in a retrospective cohort of oocyte donation recipients.
University-affiliated infertility center.
Infertile couples undergoing IVF with oocyte donation.
Main Outcome Measure(s):
CNBR per EmbR.
The CNBR increased radically (up to 64.8%) between 1 and 5 EmbR, moderately (85.2%) between 5 and 15, and slowly thereafter, reaching a plateau at 15 embryos (92.4%) and peaking after 25 EmbR (96.8%), thus demonstrating that the chances of success vary as failed attempts accumulate. Patient age was not a negative factor, and indication for oocyte donation was also irrelevant to the outcome. The data showed an overall mean number of 2.6 embryo transfers and 5.8 transferred embryos per newborn.
The relationship between CNBR and number of EmbR provides pragmatic and exact information about the probability of success with oocyte donation, which is of obvious relevance to patient counseling.