In January 2020 researchers from the USA published the results of their study to assess the effect of daily folic acid and zinc supplementation on semen quality and live birth. A total of 2,370 couples (men – average age 33 years; women – aged between 18-45 years) who were planning infertility treatment were included in the study, although only 1,773 attended the final 6-month study visit. Semen quality was assessed at the start of the study and again 6 months later whilst pregnancy information was collected 9 months after study start. The male individuals were divided into two groups, with 1,185 men receiving folic acid 5 mg and zinc 30 mg supplementation and 1,185 a placebo. Both groups received the supplementation or placebo for a period of 6 months. Results showed that the number of pregnancies was not significantly different in the two groups of individuals, with 404 (34%) females falling pregnant whose partners were taking folic acid and zinc and 416 (35%) from the placebo group. In addition, the changes in the semen quality were also not significantly different between the two groups. A further analysis revealed that the degree of DNA fragmentation was on average 28% in the folic acid and zinc group whilst it was 27% in the placebo group. It was also noted that many of those taking the folic acid and zinc supplementation experienced gastrointestinal symptoms, eg abdominal discomfort or pain, nausea and vomiting.
Schisterman EF et al. Effect of Folic Acid and Zinc Supplementation in Men on Semen Quality and Live Birth Among Couples Undergoing Infertility Treatment: A Randomized Clinical Trial. JAMA. 2020 Jan 7;323(1):35-48.