Clinical efficacy of a specific synbiotic formulation in restoring fertility in couples with persistent post-antibiotic dysbiosis: a pilot study

OBJECTIVES: To evaluate the efficacy of a specific synbiotic formulation in improving genital environment, sperm quality, and reproductive outcomes in infertile couples with a history of persistent post-antibiotic dysbiosis. METHODS: This prospective, single-arm pilot study enrolled 33 infertile couples who had completed antibiotic therapy at least three months prior without success in conceiving. Couples received the synbiotic treatment for 90 days. A strategic sexual behavior protocol (barrier contraception for the first 45 days) was adopted. Primary endpoints were changes in Sperm DNA Fragmentation (DFI via Sperm Chromatin Dispersion - SCD test), vaginal pH, and spontaneous pregnancy rates. RESULTS: At T1 (90 days), a significant reduction in mean Sperm DFI was observed (from 32.4% +/- 6.1% to 16.8% +/- 4.2%, p < 0.001). Female partners showed a significant decrease in vaginal pH (from 5.2 +/- 0.4 to 4.1 +/- 0.2, p < 0.001) and restoration of vaginal Lactobacillus dominance. The cumulative spontaneous pregnancy rate was 33.3% (11/33), with 10 pregnancies reaching full term and 1 early miscarriage. CONCLUSIONS: Modulation of the Gut-Gonad Axis via synbiotics represents a promising restorative strategy, overcoming the "biological stasis" often observed after antimicrobial treatments.