Table 2.

Inclusion and exclusion criteria for the study.

Inclusion Criteria	Exclusion Criteria
Infertility as defined by Word Health Organization standards	American Fertility Score III/IV and pre-treatment with a gonadotrophin-releasing hormone analog
Written, conscious consent of the patient	No written consent given
Age 18–45	Age < 18 or >45
Qualification and performance of the in vitro procedure	Disqualification of the patient, and excluding her from the IVF procedure in accordance with the criteria and qualifications described in the current recommendations and guidelines
No use of probiotic, prebiotic, or synbiotic preparations for at least 3 months before the examination, regardless of the form of administration	Use of probiotic, prebiotic, or symbiotic preparation for at least 3 months before the examination, regardless of the form of administration
Undergoing sample transfer procedure
No use of antibiotics in the period of at least 3 months before the examination, regardless of the form of administration	Use of antibiotics in the period of at least 3 months before the examination, regardless of the form of administration
No current or past neoplastic disease	Current or past neoplastic disease
No mental or emotional disorders	Mental or emotional disorders
Caucasian race	Race other than Caucasian
No malformations of the uterus and fallopian tubes	Previous pregnancy or miscarriage in their medical history
No vaginal infections (vaginal discharge, itching, burning, pain, bad smell)	Current or last 3 months before study vaginal infections
No endometriosis	Endometriosis
No use of hormonal contraceptives within 3 months prior to the start of their IVF intake	Used hormonal contraceptives within 3 months prior to the start of their IVF intake