Maternal KIR and Fetal HLA Influence Reproductive Success in ART-oocyte Donor.

This is an ambispective study in which healthy patients without history of RIF and RM and with indication of egg donation cycle as ART treatment will be genotyped for KIR, HLA-C and HLA-F. Male partners and egg donors will also be studied for their HLA-C alleles. Patients would be assigned to donors, following routine clinical practice, without matching based on donor's HLA-C genotype. They would undergo SET and be followed up until delivery. In addition to this prospective part, we will request access to data from patients who have equally undergone oocyte donation cycles at the clinic, who meet the inclusion criteria and who have been genotyped for KIR and HLA-C as a matter of routine practice. Combinations of maternal KIR and HLA-C genotypes of the egg donor and fetus (based on the genotypes of the donor and male partner), as well as different HLA-F SNP genotypes of the recipients (form the prospective part of this proyect) will be correlated with reproductive outcomes. LBR will be the primary endpoint of the study. In addition, secondary endpoints such as embryo development, sustained implantation, progesterone leves, implantation failure and miscarriage rate will also be evaluated. Obstetrical complications such as preeclampsia, premature birth (\<34 weeks) and low birth weight will also be evaluated.