Descriptive Analysis of Serum Immunological Markers During an Euploid Frozen Embryo Transfer in a Natural Cycle.

Exclusion Criteria12

• Body mass index lower than 18.5 or equal or higher than 29 kg/m2
• Endometriosis or adenomyosis suspected by medical history (dysmenorrhea, dyspareunia, heavy or prolonged menstrual bleeding (> 8 days), chronic pelvic pain, catamenial rectal or bladder symptoms) or diagnosed by imaging (magnetic resonance imaging or ultrasonography)
• Uterine abnormalities
• Hydrosalpinx
• Insulin resistance or diabetes mellitus diagnosed by HbA1c 5.7 %
• Antiphospholipid syndrome
• Polycystic ovarian syndrome according to Rotterdam criteria: presence of at least two of the following: irregular cycles (< 21 or > 35 days or < 8 cycles a year), biochemical or clinical hyperandrogenism, ovarian ultrasound morphology (> 20 follicles per ovary on transvaginal scan) or Anti-mullerian hormone > 5,98 ng/ml
• History of recurrent miscarriage, defined as the loss of 2 or more pregnancies according to ESHRE guidelines
• History of implantation failure, considered as the lack of pregnancy after the transfer of 2 good-quality (grade A or B for inner mass cell and trophectoderm (29)) euploid embryos
• History or suspicion of Asherman syndrome
• Autoimmune disease
• Couple first degree consanguineous