Abundance of Lactobacillus in Endometrium Affected by Chronic Endometritis

Inclusion criteria

• Infertile (≥ 12 months of unprotected regular intercourse) premenopausal women or women with ≥ 2 consecutive miscarriages undergoing hysteroscopy. - Infertile women undergoing office hysteroscopy for other reasons, such as suspected intrauterine adhesions after curettage, irregular endometrium, uterine polyps, repeated implantation failure in assisted reproduction, etc.
• Signed informed consent
• BMI ≥ 18 kg/m2 and ≤ 40 kg/m2
• Age: ≥ 18 years and ≤ 45 years
• follicle stimulating hormone (FSH) ≤ 20 (day 2-5 and estradiol ≤ 300 pmol/l)

Exclusion criteria

• Treatment with antibiotics in the past 3 months
• Treatment with immune-suppressing or immune-modulating drugs in the past 3 months
• Treatment with estrogens, progestins, contraceptives and/or antiestrogenic drugs in the cycle during which hysteroscopy is performed
• Current infection of the cervix with Chlamydia trachomatis and/or gonorrhea
• Pelvic surgery in the past 3 months
• Suspicion of malignancy
• Pregnancy
• Breast feeding
• Perimenopause (irregular menses and FSH ≥ 20 U/l on day 3-5 of the cycle)
• Outdated endometrial sample from the luteal phase (this criterion will be evaluated during visit 4 post surgery)
• Elevated progesterone concentration ≥ 20 nmol/l measured in the blood sample taken at the time of HSC.
• Insufficient amount of tissue for immunohistochemical analysis and/or microbial 16s rRNA gene sequencing