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Four Reasons Sex and Marijuana Don’t Mix

It’s easy to forget that marijuana use comes with some unwelcome side effects.

Photo purchased from iStock, used with permission.
Source: Photo purchased from iStock, used with permission.

As marijuana’s social acceptability grows, it’s easy to forget that its use can come with some unwelcome side effects. A recently released National Institute on Drug Abuse summary of marijuana research, for example, confirmed that, yes, cannabis really can be addictive, it can impair brain development, and it has been linked to a variety of mental health issues, including psychosis.

If it’s not enough that marijuana can mess with your mind, it can also mess with your sex life. Here are four ways marijuana can spoil your most intimate relationships:

1. Marijuana can affect fertility.

If being called Dad or Mom is on your bucket list, it might be time to put down the joint.

Researchers have long known that the active ingredient in marijuana, THC, can impair fertility by lowering sperm count and semen volume. It can also make sperm swim too fast too soon—a type of supercharging that causes them to burn out early and lose the energy to reach their destination. Even if the woman is the only one in the relationship using marijuana, sperm mobility can still be affected because the THC makes its way into her reproductive tract.

New research shows marijuana can also warp the shape and size of sperm, making it harder for them to reach and fertilize the egg. Of the study participants, smokers under 30—believed to be the heaviest users—were most often in the group with less than 4 percent normal sperm.

On the flip side, however, don’t count on it as birth control.

2. Marijuana has been linked to erectile dysfunction.

Although marijuana is celebrated by some of its fans as a sex booster, the studies that exist indicate it may be more likely to have the opposite effect. In other words: “It provokes the desire, but it takes away the performance,” as Shakespeare so tellingly said of that other love drug, alcohol.

One study reported double the rate of erectile dysfunction in marijuana users as nonusers. Other research noted that the dose may be key—the heavier the marijuana use, the more likely that sexual performance will be degraded. In chronic users, lower testosterone levels have also been found.

3. Marijuana can get in the way of the experience.

Marijuana is used by some during sex as a way to relax or to enhance the experience. In reality, it may just get in the way.

The relaxation that marijuana brings can actually suppress the desire to have sex. And what may seem like enhancement to the user may not be experienced the same way in a partner—for example, what feels like a marathon session in the sack may simply be the drug’s ability to play tricks with time perception.

On a more basic level, marijuana can sap the user’s interest in and commitment to an intimate connection, especially if use becomes heavy. In some cases, it becomes more comfortable for the user to have a primary emotional attachment with the drug rather than a person.

4. Marijuana’s negatives outweigh the positives.

Any positive effects that marijuana can bring to a sexual relationship are short-lived and are often followed by serious negative effects that can last weeks, months, or longer. For example, critical cognitive functions are impaired not only while the user is high but for days afterward. Marijuana can also distort judgment and lower inhibitions, which may lead to risky sexual behavior.

Marijuana can seem like an easy route to greater happiness as you’re lighting up, but it’s worth remembering that study after study has linked it to lower life and relationship satisfaction. It might be legal. It might help you unwind. But that doesn’t mean it’s good for you—or your spouse or partner.

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