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Frequently Asked Questions about Fertility
Human Effect Matrix
The Human Effect Matrix looks at human studies (it excludes animal and in vitro studies) to tell you what supplements affect fertility
|Grade||Level of Evidence [show legend]|
|Robust research conducted with repeated double-blind clinical trials|
|Multiple studies where at least two are double-blind and placebo controlled|
|Single double-blind study or multiple cohort studies|
|Uncontrolled or observational studies only|
Level of Evidence
? The amount of high quality evidence. The more evidence, the more we can trust the results.
Magnitude of effect
? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
Consistency of research results
? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.
|Notable||Very High See all 9 studies|
|Minor||Very High See 2 studies|
|Minor||Moderate See 2 studies|
- Mahdi AA, et al. Withania somnifera Improves Semen Quality in Stress-Related Male Fertility. Evid Based Complement Alternat Med. (2009)
- Gupta A, et al. Efficacy of Withania somnifera on seminal plasma metabolites of infertile males: a proton NMR study at 800 MHz. J Ethnopharmacol. (2013)
- Mayor S. Testosterone may improve sexual function and mood in older men with low levels. BMJ. (2016)
- Andrade C, et al. A double-blind, placebo-controlled evaluation of the anxiolytic efficacy ff an ethanolic extract of withania somnifera. Indian J Psychiatry. (2000)
- Chandrasekhar K, Kapoor J, Anishetty S. A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root in reducing stress and anxiety in adults. Indian J Psychol Med. (2012)
- Agnihotri AP, et al. Effects of Withania somnifera in patients of schizophrenia: A randomized, double blind, placebo controlled pilot trial study. Indian J Pharmacol. (2013)
- Raut AA, et al. Exploratory study to evaluate tolerability, safety, and activity of Ashwagandha (Withania somnifera) in healthy volunteers. J Ayurveda Integr Med. (2012)