Use of Metabolomics for the Identification of Endometrial Biomarkers for Recurrent Pregnancy Loss and Reccurent Implantation Failure Following in Vitro Fertilization.

The investigators have designed a unicentric, case-control, retro- and prospective study to compare the endometrial metabolomics profile in three groups of patients. The two case groups (RIF and IRPL) are already composed and the endometrial and blood samples already taken as part of a pre-existing research project. The current protocol concerns the control group that includes patients undergoing ART for male factor infertility.

The study will include three groups. The first group is composed of patients with a history of RIF following IVF-ET. RIF is defined as failure to obtain a clinical pregnancy (fetal cardiac activity at 6-7 weeks gestational age (GA)) following at least 3 different transfers of at least 4 good quality embryos (fresh or frozen).

The second group comprises patients with a history of IRPL, defined as three or more consecutive pregnancy losses that occurred before 14 weeks gestational age. Early pregnancy losses diagnosed before ultrasonographic confirmation will be included.

The third group will include patients undergoing ART for male factor infertility.

The study protocol will be presented and explained to all eligible patients in the control group during the routine consultation before treatment. Patients who agree to participate will contact the department to program the inclusion visit with one of the attending physicians in the department, during which the blood and endometrial samples will be taken. The inclusion visit will take place at the department of reproductive medicine of Angers University Hospital around day 21 of the menstrual cycle (in the middle of the implantation window, which occurs between day 19 and 23 of the cycle, day 1 being the first menstruation day).