• A multi-center, randomized, placebo-controlled trial is underway to investigate the efficacy of synbiotic supplementation in preventing spontaneous preterm birth (sPTB).
• Pregnant women at risk for sPTB between 80/7 and 106/7 weeks of gestation will receive either a synbiotic containing eight Lactobacillus strains or a placebo daily until delivery.
• The primary outcome is gestational age at delivery, with secondary outcomes including PTB rates, PPROM rates, vaginal microbiome analysis, and neonatal outcomes.
• The trial aims to recruit 402 participants across seven Belgian teaching hospitals over approximately 36 months to determine if synbiotics can prolong pregnancy and improve neonatal health.