I have been getting a lot of questions about male fertility supplements and whether or not they work or are worthwhile.
Although there are many different formulations currently on the market, the key ingredient common to most of these is some form of L-carnitine. Many studies have been published to demonstrate acetyl-L-carnitine improves sperm motility, some show an increase in count and volume as well(1)(2)(3)(4). Researchers at the University of Rome led by Dr. Andrea Lenzi demonstrated in a placebo controlled, double-blinded study that L-carnitine/acetyl-L-carnitine was effective in improving sperm motility.(5) In this study, men who took L-carnitine and acetyl l-carnitine had increases in sperm concentration, forward movement, and total movement. The authors concluded that “combined treatment with L-carnitine and acetyl l-carnitine... was effective in increasing sperm motility, especially in groups with lower baseline levels (of moving sperm)”. Metabolism studies imply that acetyl-L-carnitine (also referred to as ALCAR) is better absorbed than L-carnitine or L-carnitine fumarate and so is potentially up to 17x more effective by weight. The exact mechanism if L-carnitine’s effect is not know with certainty. There is speculation the motility effect is due to improved mitochondrial function. The mitchondria are the energy generating organelles in cells. There is also some evidence that L-carnitine improves signal transduction at the testosterone receptor.
An additional study demonstrates that zinc and folic acid improve sperm motility and count in both fertile and infertile men.(6) Zinc’s role in sperm production and testosterone activity has been well described.(7)
Several studies also point to an important role for antioxidants such as vitamins E and C as well as some B vitamins in normal sperm production, function and genetic integrity.(8)(9)
So, I say why not take a good male supplement in preparation for IVF/ICSI/PGD. Ideally it should be started 80-90 days and can be taken for up to 6 months prior to treatment. Shorter courses may also be beneficial.
Here is a link to a page that compares some of the popular formulations:
We typically recommend Naturally Smart for Men because it has more of the active ingredients than the others and is half as expensive as the next best (Proxeed). Naturally Smart comes in a capsule form whereas Proxeed is a powder that is mixed with juice and does not taste great. The key is the amount of acetyl-L-carnitine as it has 17x greater bioavailability than L-carnitine fumerate.
Links about L-carnitine:
1. Fertility and Sterility. 2005 83:355-361.
2. Andrology. 2004 Sep-Oct;25(5):761-70.
3. Drugs Under Experimental Clinical Research. 1995;21(4):157-9.
4. Andrologia 1994 May;26(3):155-9.
5. Fertility and Sterility. 2004 June; 81:1578-84.
6. Fertility and Sterility. 2002 March;77:491-8.
7. Proceedings of the National Academy of Science U S A. 2009 Jun 30;106(26):10859-64.
8. Human Reproduction. 2008 May;23(5):1014-22.
9. Journal of Andrology. 2005 Jul-Aug;26(4):550-6.