The Effects of Alpha-Lipoic Acid Supplement on Sperm Parameters and DNA Fragmentation in Couples with Recurrent Pregnancy Loss: A Randomized Controlled Trial.

Abstract

Objective: Previous studies have shown that the level of oxidative stress in individuals with recurrent pregnancy loss (RPL) is significantly higher than in fertile individuals. Alpha-lipoic acid (ALA) has been considered an antioxidant that can improve male fertility. This study aimed to investigate the antioxidant effect of ALA on sperm parameters and DNA fragmentation index (DFI) in couples with a history of RPL.

Materials and methods: In this randomized, double-blind clinical trial, 64 couples with a history of RPL, who were referred to the Milad Infertility Center, Mashhad, Iran, between February 2021 and March 2022, initially enrolled. Of these, 40 couples completed the three-month follow-up and were included in the final analysis. The intervention group received ALA and folic acid for three months, while the control group received a placebo and folic acid for the same duration. Baseline sperm parameters, including concentration, motility, and morphology, were assessed alongside the sperm DFI before and three months after the intervention.

Results: There were no significant differences in baseline characteristics between the two groups (P>0.05). After three months, however, sperm concentration, motility and morphology significantly improved in the intervention group. In contrast, while sperm concentration improved in the control group, no significant changes were observed in sperm motility or morphology. There were no significant differences between the two groups regarding sperm parameters before and after the intervention (P>0.05). DFI showed a significant reduction in the intervention group compared to the control group (P<0.05).

Conclusion: ALA supplementation appears to positively influence sperm parameters and reduce DFI within individuals in couples with a history of RPL. While within-group improvements were noted, between-group differences in sperm concentration, motility, and morphology were not statistically significant. These findings suggest a potential role for antioxidant therapy in the management of male infertility, though further studies are needed to confirm efficacy (registration number: IRCT20181030041503N4).