| Table 1. Description and main results of the studies included in the systematic review. | |||||
| Author/Year | Design | No | follow-up time | Intervention | Results |
|---|---|---|---|---|---|
| Valcarce et al. (2017) | Randomized | 9 | 6 weeks | L. rhamnosusCECT8361 + B. Longum CECT7347 (109 CFUs) | ↑ sperm motility, ↓ DNA fragmentation and levels H2O2 intracellular of the sperm. |
| Maretti & Cavallini (2017) | Randomized, double-blind, placebo-controlled | 41 | 24 weeks | L. paracaseiB21060 (5 x 109 CFUs) + arabinogalactan 1243 mg + fructooligosaccharide 700 mg + L-glutamine 500 mg | ↑ ejaculate volume, concentration, motility, number of spermatozoa ejaculated and percentage of typical shapes. ↑ FSH, LH and T levels. |
| Helli et al. (2022) | Randomized, double-blind | 50 | 10 weeks | L. casei, L. rhamnosus, L. bulgaricus, L. acidophilus, B. breve, B. longum, S. thermophiles (2 x 1011 UFCs) |
↑ Ejaculated volume, total sperm count, concentration, total motility, percentage of motile sperm. ↑ TAC and plasma MDA concentration. ↓ CRP and TNF-α. ↑ testosterone and ↓ FSH, LH and PRL, but not significant. |
| Abbasi et al. (2021) | Randomized, triple-blind | 47 | 11.4 weeks | L. rhamnosus, L. casei, L. bulgaricus, L. acidophilus, B. breve, B. longum, S. thermophilus(109 CFUs) and fructooligosaccharides. | ↑ sperm concentration, motility and normal morphology. ↓ lipid peroxidation and DNA fragmentation. |
FSH = Follicle Stimulating Hormone; B = Bifidobacterium; E2 = estradiol; L = Lactobacillus; LH = Luteinizing hormone; MDA = Malondialdehyde; PRL = Prolactin; CRP = C-Reactive Protein; S = Streptococcus; TAC = Total Antioxidant Capacity; T = Testosterone; TNF-α = tumor necrosis factor α; CFU= Colony-forming unit.