Tiny bacteria, big impact on IVF? new study investigates

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Man aged 18 to 59 who have provided a sperm sample after an abstinence period of between 2 and 7 days. Sperm prepared by density gradient on day 0. Negative sperm culture (\<6 months). No specific urogenital history (varicocele, cryptorchidism, testicular ectopia, etc.). * Women aged 18 to 43 undergoing oocyte puncture with collection of follicular fluid on day 0. No endometriosis or hydrosalpinx. Negative vaginal sample (\< 6 months). * Negative HIV, HBV, and HCV serology tests within the last year. * Absence of urinary tract infections in men and sexually transmitted infections (HPV, HSV, HIV-1/2, C. trachomatis, Gonorrhea, Syphilis, etc.) (\<6 months). * Absence of recent antibiotic or antifungal treatment (end of treatment \< 3 months) Absence of probiotic intake (\< 3 months). * No history of chemotherapy or radiation therapy. * Embryonic culture performed up to day 6 for all zygotes. Exclusion Criteria: * Homosexual patient couples or transsexual couples * Patients treated for medically assisted procreation with a third-party donor * Frozen sperm pellets (ejaculate or surgical) * Donor sperm * Sperm prepared by washing * Abstinence period \<2 or \>7 days * Fever \<3 months * History of chemotherapy or radiotherapy. * History of urinary tract infections in man (\< 6 months) * History of sexually transmitted infections (HPV, HSV, HIV-1/2, C. trachomatis, gonorrhea, syphilis, etc.) (\<6 months) * Specific urogenital history (varicocele, cryptorchidism, testicular ectopia, etc.) * Recent antibiotic therapy or antifungal treatment (end of treatment \< 3 months) * Taking probiotics (end of treatment \< 3 months) * Positive sperm culture \< 6 months. * Positive vaginal sample \< 6 months. White puncture. * Collection failure. * Fertilization failure