An estimated 43 percent of women and 31 percent of men suffer from some degree of sexual dysfunction, broadly defined as any problem that occurs during the sexual response cycle — excitement, plateau, orgasm and resolution — that causes dissatisfaction for the individual or couple.

Three categories of sexual dysfunction make up the majority of problems: disorders of desire, arousal and orgasm.

Deficits in desire usually manifest as a lack of interest in sex. The most common arousal complaint is an inability to become physically excited during sexual activity. Concerns related to orgasm include an inability to have an orgasm or a delay in reaching orgasm that causes distress.

The causes of sexual problems vary. Some are biological or medical in nature, while others have psychological origins. Although service members and veterans generally are not at greater risk of developing sexual problems than their civilian counterparts, there is a common factor that contributes to the sexual dysfunction of many: post-traumatic stress disorder.

The connection between PTSD and sexual dysfunction has been studied for decades and with increasing interest over the past several years. The increased interest as of late is a direct result of the wars in Iraq and Afghanistan and the hundreds of thousands of veterans who have been diagnosed with the trauma-based disorder.

Individuals suffering from PTSD often are highly anxious. Anxious people produce excessive amounts of hormones and neurochemicals. Some of these substances negatively affect sexual functioning by constricting blood vessels and blood flow, both which are important to sexual health.

Feeling emotionally disconnected from loved ones is a core symptom of PTSD. For many, loving feelings for a spouse or partner are few or absent. And without that emotional connection, it's difficult to develop and maintain intimacy, which is the bedrock of a healthy sexual relationship.

A common treatment for PTSD is medications that regulate the level of the chemical serotonin in the brain. Serotonin plays an important role in sexual functioning. When taking these medications, men and women sometimes report delayed or absent orgasms and reduced interest in sex. For men, it's not uncommon to hear complaints of difficulty achieving or maintaining an erection.

The relationship between PTSD and sexual dysfunction is complex. A number of factors can contribute to sexual problems, which can cause significant distress for the person or couple. However, the fix is often relatively simple. It may include individual or couples therapy or a switch to a different medication. The first step is to talk with your health care provider.

Bret A. Moore, Psy.D., is a board-certified clinical psychologist who served two tours in Iraq. Email him at kevlarforthemind@militarytimes.com. This column is for informational purposes only and is not intended to convey specific psychological or medical guidance.