O-263 Effect of clindamycin and a live biotherapeutic containing lactobacilli on the reproductive outcomes of IVF patients with abnormal vaginal microbiota: a double-blind, placebo-controlled multicentre trial

Abstract Study question Does treatment of abnormal vaginal microbiota improve the reproductive outcomes IVF patients? Summary answer Data is being analysed and will be presented at ESHRE 2023. What known already An increasing number studies reported an association between genital tract adverse in patients. One hypothesis could that ascend to endometrium where hampers implantation. To best our knowledge, this first study powered investigate causality - defined by a bacterial vaginosis like clinical pregnancy rate design, size, duration Double-blind, placebo-controlled multicentre trial patients diagnosed with subsequently randomised into three parallel groups 1:1:1. The group received clindamycin 300 mg ×2 daily for 7 days followed Lactobacillus crispatus until scan. second placebo, whereas third placebo/placebo. A total 1518 were screened, 338 randomised. was from 2017 Participants/materials, setting, methods any cause infertility embarking on their first, or stimulation cycle embryo transfer approached inclusion. At minimum 12 prior transfer, screened qPCR assay, targeting high quantitative loads Fannyhessea vaginae Gardnerella spp. Patients excluded if they had intrauterine malformations polyps, septum, fibroma. Main results role chance safety monitoring board has decided not open randomization code yet. final dataset completed. Limitations, reasons caution Wider implications findings present drug intervention used live biotherapeutic containing crispatus. have worldwide important impact practice as currently there no evidence screening treating improves outcome. Trial registration EudraCT 2016-002385-31