OBJECTIVE: Sperm DNA damage has been associated with adverse reproductive outcomes. Sperm vitality is especially important to measure if sperm motility is low, so differentiate between live non-motile sperm and dead sperm. L-carnitine (L-C) is essential for the normal mitochondrial oxidation of fatty acids, protects cell membrane and DNA against free oxygen radicals damage.
DESIGN: This was a randomized, double blind, placebo controlled (DBPC) study and it examined the effect of test formulation (Proxeed Plus), containing L-C 2g and acetyl-L-carnitine (ALC) 1g, in men with idiopathic oligo-asthenozoospermia. The protocol was 2 months wash-out and 6 months treatment (T-2, T0, T+3, T+6), with test formulation (125 patients) or placebo (50 patients).
MATERIALS AND METHODS: Analysis of ejaculate was done according to WHO 5th guideline. Progressive sperm motility (A+B grade of rapid) was done manually. DFI was evaluated by Halosperm kit (Halotech DNA, S.L,) and sperm vitality was done by the one-step eosin-nigrosin technique.
RESULTS: The values at different time points were: sperm vitality (%): T0=0.52 (0.43-0.60), T3= 0.57 (0.46-0.64) and T6=0.56 (0.56-0.65; DFI (%): T0=38,50 (32,00-48,75), T3=35,50 (25,50-44,00) and T6=31,00 (25,00-41,00); the progressive sperm motility (%): T0=28.00%(12.00±38.00), T3=30.00% (12.00±39.00) and T6=31.00% (20.00±41.00); all parameters showed significance of p<0.001 by Friedman test. The increase of spermatozoa vitality has the best predictive and diagnostic characteristics and those men who have increased this parameter by 1% have 1,119 times more likely to have a progressive motility of spermatozoa greater than 20% after 6 months of therapy. If the spermatozoa vitality, after six months of therapy increases by 5.9% and more (cut off value), the probability that sperm motility will be greater than 10% or 20% is 100% (PPV = 100%). If DFI drops by more than 3% (cut-off), after 6 months of therapy, it can be expected, with moderate accuracy, that men have sperm motility greater than 10% (AUC=0.793; p<0.001). DFI reduction (odds ratios=1.106 with 95% confidence intervals) independently increases the likelihood that sperm motility is >10%. In In placebo group there was no significant difference in sperm motility, vitality and DFI, between T0 and T6.
CONCLUSIONS: This DBPC study demonstrated that increase of percentage of sperm vitality and decrease o DFI are good predictors of improvement of progressive sperm motility in oligoasthenonospermic men treated with antioxidant therapy.