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.
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MAP posted-by: Jay Bergstrom