Pubdate: Tue, 17 Jun 2014 Source: Washington Post (DC) Copyright: 2014 The Washington Post Company Contact: http://mapinc.org/url/mUgeOPdZ Website: http://www.washingtonpost.com/ Details: http://www.mapinc.org/media/491 Author: Linda Searing Page: E3 MARIJUANA MAY AFFECT SIZE AND SHAPE OF SPERM, INHIBITING FERTILITY THE QUESTION Marijuana has been shown to have a negative effect on memory and brain development but is believed to be potentially therapeutic for people with medical conditions or treatments that cause nausea, chronic pain or inflammation. What effect might marijuana have on a man's fertility? THIS STUDY included 1,970 adult men who had been trying to conceive for at least 12 months unsuccessfully. They had no medical conditions that affected fertility and had not undergone treatments that could have caused infertility. Analysis of semen samples found that 318 of the men had poor sperm morphology, meaning that less than 4 percent of their sperm were normal in shape and size. Men who had used marijuana in the three months before producing the sperm samples were about 1-1/2 times as likely to have abnormal sperm as were men who had not used marijuana. The effect was strongest among younger men, with risk for abnormal sperm doubling among marijuana users younger than 30. WHO MAY BE AFFECTED? Men who want to conceive a child. About a third of the time, infertility stems from the male partner. To ensure fertility, sperm morphology matters, as do sperm volume and motility (how well they move), hormone production and a blockage-free delivery system to get sperm into semen. Injuries, chronic health problems, medication and structural or functional problems with reproductive organs are among the elements thought to play a role in infertility. Sometimes a cause cannot be determined. CAVEATS Information on marijuana use came from the men's responses on questionnaires and in interviews. The authors wrote that it "seems likely that the more marked effect in younger men reflected greater quantity of consumption" of marijuana, but that remains unclear because the study did not include data on frequency of use. The study did not determine whether stopping marijuana use would improve the odds of conception. FIND THIS STUDY June 4 online issue of Human Reproduction, humrep.oxfordjournals.org LEARN MORE ABOUT male infertility at www.urologyhealth.org and www.familydoctor.org. The research described in Quick Study comes from credible, peerreviewed journals. Nonetheless, conclusive evidence about a treatment's effectiveness is rarely found in a single study. Anyone considering changing or beginning treatment of any kind should consult with a physician. - --- MAP posted-by: Jay Bergstrom