I am turning 30, and my wife just turned 35. We have been trying for pregnancy for six months. I (not my wife) am a recreational marijuana smoker (once per day). I've been reluctant to quit, as we have many friends who also use marijuana and have not experienced any problems starting their families and having beautiful children. Could the marijuana be preventing us from conceiving? Even if it isn't, is casual marijuana use as harmful as cigarette smoking would be?

Kevin

Both marijuana and cigarettes are associated with breaks in the DNA of sperm. The more you smoke, whether it is marijuana or tobacco, the more DNA breaks occur. The effect does not seem to be greater with marijuana. However, marijuana is metabolized in the liver, and unlike tobacco, it can affect the liver over the long term in such a way as to increase estrogen levels. Higher estrogen levels in males can increase the risk of abnormal sperm counts or motility. If your semen analysis is normal, this is not likely an issue.

I would strongly recommend antioxidants to any male smoker, regardless of which weed they wish to inhale. Both tobacco and marijuana can lower the antioxidant potential of the seminal fluid, which can adversely affect the sperm.

While I am not aware of any studies that show that minimal or infrequent recreational smoking can impair fertility or result in birth defects, it is still a good idea to cut out any potential factors that might hinder the chance of successfully achieving conception.