Assisted Reproductive Technologies (ART) Failures: Is It the Seed or the Soil?

Assisted reproductive technologies (ART) have accomplished spectacular progresses over the last few years, leading to sustained implantation rates (sIR) [Formula: see text]60% following euploid blastocyst transfers. These results raise new challenges for infertility specialists, notably the ability to care for infertile couples who fail ART, sometimes recurrently. ART failures may be due to disorders residing in the endometrium (the soil) or embryo (seed). To simplify the review of this dilemma and limit variables, we focused our research on the outcome of euploid blastocysts transfers conducted in E2 and i.m. progesterone replacement cycles. This methodological choice for our research should not be confused with a therapeutic recommendation in case of ART failures. The sum of the data collected indicates that if recurrent implantation failure (RIF) exists, it is extremely rare, affecting only [Formula: see text]5% of ART couples.