<p>The British&nbsp;<i>National Surveys of Sexual Attitudes and Lifestyles (</i>Natsal) have been undertaken decennially since 1990 and provide a key data source underpinning sex
Additional file 3. Comparison of semen parameters in potential sperm donors and in men from infertile couples. Statistically significant data (P-value < 0.05) are shown in bold.
5, 10-Methylenetetrahydrofolate reductase (MTHFR) is a crucial enzyme in the folate metabolic pathway with a key role in generating methyl groups. As MTHFR deficiency impacts male fertility and sperm
