The Cornell Medical Center's Peter Schlegel and Cigdem Tanrikut have published a new study linking antidepressants with reduced male fertility. The drugs which are prescribed to millions of American men are though to impair fertility by damaging the sperm's DNA. This new study follows on from a 2006 project at the Cornell Medical Center in New York City in which two male patients had developed low healthy sperm counts having been prescribed two different selective serotonin-reuptake inhibitors (SSRIs). SSRIs are the most common prescribed class of antidepressant drugs.