Table 2.
Description and summary of data from 19 studies that investigated associations between folate and sperm quality and sperm epigenetics
| Author | Year | Study type | Synthetic/natural folate | Sperm parameters | Sperm epigenetics | Sperm DNA damage | Sperm apoptosis |
|---|---|---|---|---|---|---|---|
| Lambrot et al. | 2013 | Animal study | Synthetic | = | +/− | − | = |
| Swayne et al. | 2012 | Animal study | Synthetic | = | − | ||
| Ly et al. | 2017 | Animal study | Synthetic | +/− | +/− | ||
| Yuan et al. | 2017 | Animal study and case‐control study |
Synthetic Natural |
+ + |
= | ||
| Murphy et al. | 2011 | Case‐control study | Natural | + | |||
| Wallock et al. | 2001 | Case‐control study | Natural | + | |||
| Boxmeer et al. | 2007 | Cross‐sectional study | Natural | = | |||
| Boxmeer et al. | 2009 | Cross‐sectional study | Natural | − | − | ||
| Crha et al. | 2010 | Cross‐sectional study | Natural | = | |||
| Ebisch et al. | 2006 |
Randomized controlled trial. Data used is cross‐sectional |
Synthetic | = | |||
| Ebisch et al. | 2005 | Randomized controlled trial | Synthetic | = | |||
| Boonyarangkul et al. | 2015 | Randomized controlled trial | Synthetic | + | − | ||
| Da Silva et al. | 2013 | Randomized controlled trial | Synthetic | = | |||
| Raigani et al. | 2014 | Randomized controlled trial | Synthetic | = | = | ||
| Wong et al. | 2002 | Randomized controlled trial | Synthetic | = | |||
| Chan et al. | 2017 | Retrospective intervention study | Synthetic | = | |||
| Landau et al. | 1978 | Prospective intervention study | Synthetic | = | |||
| Aarabi et al. | 2015 | Prospective intervention study | Synthetic | = | +/− | = |
+, positive association; −, negative association; =, no association.