Improvement in human semen quality after oral supplementation of vitamin C.
Level 4 - case-series / case-control
Uncontrolled, open-label before-and-after study (case series) without a control group.
PubMed 17004914 · doi:10.1089/jmf.2006.9.440
What was done
Thirteen infertile men aged 25 to 35 years with oligozoospermia (and no genital infection or varicocele) were enrolled in an open-label trial. Participants took 1,000 mg of vitamin C orally twice daily for up to two months. Sperm count, motility, and normal morphology were assessed before and after treatment.
What was found
After two months of vitamin C supplementation, mean sperm count increased from 14.3 ± 7.38 × 10⁶/mL to 32.8 ± 10.3 × 10⁶/mL (P < .001). Mean sperm motility increased from 31.2 ± 9.61% to 60.1 ± 8.47% (P < .001), and mean normal morphology increased from 43 ± 7.87% to 66.7 ± 4.77% (P < .001).
Why it matters
This study provides preliminary observational evidence that high-dose oral vitamin C supplementation may improve conventional semen parameters in infertile men with oligozoospermia.
Limits
The study had a very small sample size (n = 13) and lacked a control or placebo group, leaving open the possibilities of placebo effects, lifestyle confounders, or regression to the mean. Pregnancy rates and live birth outcomes were not evaluated.
Cited by
- supports In a study of 13 infertile men taking 1 gram of oral vitamin C twice daily for two months, sperm count increased by 58% and sperm motility increased by 48%.