[Embryo stage impact on the risk of ectopic pregnancy after In Vitro Fecondation]

Objectives: Ectopic pregnancies are still the first mortality cause of the first semestre of pregnancy. They are much more frequent in IVF (2-5%) than in the standard population (1-2%). The aim of this study was to compare the rate of ectopic pregnancies following a fresh embryo transfer done whether at an clived embryo stage (day 2 or 3 of the embryo development) or at a blastocyst stage (day 5 or 6 of the embryo development).

Methods: This is a monocentric retrospective study including all 18 to 43 year-old patients getting pregnant (ßHCG>100 UI/L) after a fresh embryo transfer from In Vitro Fecondation with or without Intra-Cytoplasmic Sperm Injection, between January 1st 2014 and December 30th 2020 in the Hospital of Besançon (France). This population has been divided into 2 groups according to the embryo stage on the day of transfer.

Results: Nine hundred and twenty two patients have been included. There were statistically more ectopic pregnancies after a blastocyst transfer (n=4; 5.4%) than after a clived embryo transfer (n=14; 1.7%). (P=0.049) CONCLUSION: In our population, there were more ectopic pregnancies from blastocyst(s) transfers than from clived embryo(es).