A Fertile Imagination? Paxil May Damage Sperm

Posted on Mar 3, 2009 in Health & Wellness

A group of 35 healthy men who were given Paxil over a five-week period had higher levels of sperm with damaged DNA, according to a report in New Scientist.*

Researchers at Cornell Medical Center in New York who, two years ago reported two men developed low counts of healthy sperm after taking two antidepressants, examined sperm before Paxil was given and again four weeks later.

They found the men’s sperm seemed healthy – amounts of sperm and semen, and the shape and motility of sperm, were all normal. But after examining DNA fragmentation in the sperm, they noticed the proportion of sperm cells with fragmented DNA rose from 13.8 per cent before taking Paxil to 30.3 per cent after just four weeks, according to the mag.
In couples undergoing IVF, studies have found that where the man has more sperm with damaged DNA, fewer embryos form and those that do are less likely to implant successfully into the woman’s uterus, the mag writes. As a result, fertility specialists regard a fraction of 30 per cent of sperm with DNA damage as being “clinically significant”, Douglas Carrell, a specialist in male infertility at the University of Utah in Salt Lake City, tells the mag.

The Cornell researchers, led by Peter Schlegel, are concerned some men currently taking Paxil and other SSRI antidepressants may be suffering damage to their fertility. Results will be presented in November at a meeting of the American Society for Reproductive Medicine in San Francisco, California.

A spokeswoman for Glaxo, which sells Paxil, known as Seroxat in the UK, tells the mag: “This study was not conducted by GSK, and therefore we are currently reviewing the investigators’ findings. We take seriously our responsibility to ensure our medicines are used safely.”

However, a fertility specialist says the results were a “cause for concern.” Allan Pacey, senior lecturer in Andrology at the University of Sheffield, tells the BBC there had been “sporadic reports” that antidepressants could affect semen quality, but more research would be needed to evaluate risks.

“The apparent increase in sperm DNA damage is alarming, although the level at which we think the damage becomes clinically significant is controversial to many scientists,” he tells the BBC. “”It is a shame that the authors appear not to have conducted a randomised controlled trial which would be the most scientific way to investigate the drugs effects, but I agree that the results are of concern and need to be investigated further.”

Marjorie Wallace, from the mental health charity Sane, tells the BBC that patients should wait for larger studies: “While these results may be worrying for people taking antidepressants who hope to conceive, it is important to note that this is a preliminary study with a small sample group.

“We would be worried if this study caused patients to stop their treatment and would urge anyone with concerns to consult their doctor. Antidepressants can be a lifeline for many people, and the risk of relapse must be borne in mind in balancing the risks and benefits of these drugs.”

Andrew McCulloch, of the Mental Health Foundation, tells the Beeb: “Most medications carry some level of risk, and antidepressants are no different. They are powerful drugs, so in a sense it is no surprise that research is discovering more about their impact on the body. More investment is needed in other mental health treatments such as talking therapies and exercise therapy.

“However, we should remember that SSRIs have changed many lives for the better and that any decision about changing or stopping your medication should be discussed with your doctor.”

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