Testosterone replacement therapy in theory has a negative effect on sperm counts in reproductive men.
As a result men who still want to have kids have to look for alternative treatments to taking testosterone. The current regimen for men who want to have kids is to use HCG 500 units daily subcutaneous injection.
Background: Testosterone is produced primarily in the testicles in men. A hormone called Luteinizing Hormone (LH) produced in the pituitary gland in the brain is what signals the testicles to make testosterone. The pituitary gland acts like a thermostat. It senses how much testosterone their is in the blood. If the levels are low then it makes more LH which tells the testicles to make more testosterone. If testosterone levels are high then the pituitary gland slows down production of LH (LH levels are low).
To try and make this simple (not 100% correct from a physiologic standpoint), testosterone also can have a negative feedback on Follicle Stimulating Hormone secretion (FSH) from the pituitary gland. FSH is primarily responsible for telling the testicles to make sperm. So when we give men testosterone via a cream or injection, it can negatively effect sperm production since levels in the blood are high.
HCG stands for Human Chorionic Gonadotropin and is a hormone of pregnancy. It works almost exactly like LH in men, it tells the testicles to make BOTH testosterone and sperm. So men with low testosterone levels tell their doctor that they still prefer to have children this is what it typically prescribed. The reason why we do not use this in all men is that HCG stops working in men around the age of 45 (varies). This is because the testicles simply don’t have the capability to continue to make more testosterone (due to aging).
What we see in practice is that most men who use testosterone can still maintain fertility and get their wives pregnant. I was on testosterone only for 6 months prior to my wife becoming pregnant back in September. But to be safe doctors will always caution patients about potential fertility issues.
What happens if men use HCG and they don’t get a huge bump in their testosterone levels? What I typically do is give them testosterone AND HCG at the same time. A typical regimen will be to use 1 gram of a 200mg Lipoderm cream in the morning and inject 1000 units of HCG every other day. This will keep testosterone high AND preserve sperm counts.
The Journal of Urology just published a study (Feb 2013) which looked at men (average age 26) who they gave testosterone injection to AND HCG 500units every other day. The results demonstrated that this regimen maintained excellent levels of testosterone and did not adversely effect sperm counts. This study is very encouraging and further supports the utility of testosterone replacement in younger men.
I recently had a 25 year old male patient with no libido and erectile dysfunction who had testosterone levels of 275 (range 348-1198). Because he was a professional athlete he was not able to use testosterone despite having significant symptoms. For him I prescribed 500 Units of HCG daily. In one month I will retest his levels and if they are optimal keep him on this dose. If not the plan will be to add the morning testosterone cream and use the HCG to maintain sperm counts.
The reality of what I see in my practice is that younger men can and do suffer from low testosterone. There are many things that can cause this but regardless the treatment is to give them testosterone. We now understand that sperm counts can be preserved through the use of HCG.
I hope that helps.