New Cornell Study: Selective serotonin anti-depressants significantly lower male sperm count

Fertility experts say new evidence that some SSRI anti-depression drugs may cause fragmentation of the sperm DNA could help explain why so many couples are struggling to conceive. US research published in the latest New Scientist magazine has found that the drug paroxetine, marketed under the trde names Seroxat, Paxil, Parotin, Aropax, Xetanor, ParoMerck, Rexetin) significantly lowers sperm quality. 

The team from Cornell Medical Centre in New York put 35 healthy men on the drug for five weeks, with examinations four weeks showing no change in sperm quantity, shape or movement. But a closer examination found that on average, the proportion of sperm cells with fragmented DNA rose from 13.8 per cent before taking paroxetine to 30.3 per cent after just four weeks. The lead researcher Peter Schlegel said the statistics were “clinically significant”, as it took men from relatively fertile to essentially infertile. 

Professor Michael Chapman, director of infertility at IVF Australia, said there was a growing body of evidence to suggest new generation antidepressants known as selective serotonin reuptake inhibitors (SSRIs) affect fertility. “This is something we’ve suspected for a while, with more evidence pointing in this direction,” Prof Chapman said. Statistics show an increasing number of men are being medicated for depression, with about 12 million prescriptions written each year. Drugs in this class include (trade names in parentheses):

  1. citalopram (Celexa, Cipramil, Dalsan, Recital, Emocal, Sepram, Seropram)
  2. dapoxetine (no trade name yet; not yet approved by the FDA)
  3. escitalopram (Lexapro, Cipralex, Esertia)
  4. fluoxetine (Prozac, Fontex, Seromex, Seronil, Sarafem, Fluctin (EUR), Fluox (NZ), Depress (UZB))
  5. fluvoxamine (Luvox, Fevarin, Faverin, Dumyrox, Favoxil, Movox)
  6. paroxetine (Paxil, Seroxat, Sereupin, Aropax, Deroxat, Rexetin, Xetanor, Paroxat)
  7. sertraline (Zoloft, Lustral, Serlain)
  8. zimelidine (Zelmid, Normud)

Prof Chapman said the use could be contributing to the increasing number of Australian couples with infertility problems. “However, anti-depressant use tends to be relatively low, about five per cent, among men seeking fertility treatment, so it’s not the main driver.” Sydney reproductive specialist Dr Anne Clark said affected men could talk to their GPs about non-SSRI antidepressants, or try other methods to improve sperm quality. “There are lots of things that help, like more frequent ejaculation, taking antioxidants, stopping smoking and reducing alcohol,” Dr Clark said. “We also know that if a man puts on just nine kilos of weight then that can seriously affect his sperm quality too.” 

The pharmaceutical company GlaxoSmithKline, which markets paroxetine, said it was currently reviewing the investigators’ findings.