Why Does Sex Have a Smell? 8 Things That Can Cause Odor

It's common for sex to have a smell. This intimate activity can include vaginal secretions, semen, a lubricant, or a latex condom—not to mention sweaty humans—that all have a unique smell. Here are some common reasons sex may smell, plus after-sex smells that may warrant a visit to your healthcare provider. 

Post-sex smells can vary from person to person, and whether you have a penis or a vagina. Let’s say sex smells completely off or is particularly foul. In that case, there could be an underlying health-related reason, like a sexually transmitted infection.

You can typically blame sex smells on bodily fluids and infections. But it's not abnormal to notice a smell during sex when you're healthy, too. 

Semen and Penis Odors

If you or your partner has a penis, semen can have a distinct smell similar to bleach, chlorine, or ammonia. This odor is likely due to semen's slightly alkaline pH and the alkaline substances that make up semen, like calcium, magnesium, and zinc. It's also normal for healthy sperm to have no smell. 

If you or your partner has an uncircumcised penis, trapped bacteria or skin cells, oil, and moisture build-up—aka smegma—under the foreskin can also cause a smelly odor. Making sure to clean the foreskin will make the smell go away. But, if you notice persistent foul odors, redness, abnormal discharge, or irritation in your penis (circumcised or uncircumcised), visit your healthcare provider. You could have a sexually transmitted infection (STI) or bacterial infection.

Vaginal Odors

Vaginal fluids don't typically have a noticeable scent, but a healthy vagina can have a unique smell. If you notice a tangy or sour vaginal smell—similar to fermented food like sourdough bread—don't panic. This is a typical scent caused by the vagina's slightly acidic pH and its "good" Lactobacilli bacteria.

A healthy vagina can also smell slightly different depending on the stage of your menstrual cycle and your unique aroma. If you're having period sex, you may also notice a metallic or copper scent similar to a penny. This is from the iron content in your menstrual blood. If you're not on your period and notice this smell, you may be experiencing some light bleeding after sex from vaginal dryness or intense sex. 

Sweat or Body Odor

Sex can be a pretty sweaty activity so you may notice a musky odor, especially if you haven't showered before starting sex. This scent could come from your armpits or genital area.

Sweat glands and hair follicles around the genitals can hold onto bacteria and cause some unpleasant smells. Keeping your entire body clean before sex can help ward off lingering bacteria smells. But like any form of exercise, it's also normal for your genital area to get sweaty and smelly during sex.

New Sex Partners

If you have a vagina and notice a new or stronger sex smells with a new sex partner, this can be due to your new partner’s different levels of bacteria which can alter your vagina's bacterial environment.  Using sex toys and spermicides can also alter your vagina's scent.

"Not all odors are bad," Sherry Ross, MD, an OB-GYN and author of She-ology: The Definitive Guide to Women's Intimate Health. Period told Health. "But if the odor is persistent for days following sex and you are experiencing other symptoms including a vaginal discharge, itching, redness, and vulvar swelling, you should see your healthcare provider." 

If you notice any of these symptoms and a foul smell after having sex with a new partner, you could be dealing with an infection.

Bacterial Vaginosis

If you or your partner have a vagina and notice a fishy smell, one of you could have bacterial vaginosis (BV). BV occurs when there is an overgrowth of certain bacteria in the vagina. You're more likely to get BV if you have multiple sex partners, a partner with a vagina, or a new sex partner. 

Many people with BV don't have symptoms, but BV symptoms typically include:

• Thin white or gray discharge
• Pain
• Itching
• A fishy odor that's especially strong after sex. 

See your healthcare provider for treatment if you notice any of these symptoms. BV increases your risk of contracting other sexually transmitted infections (STIs) if left untreated.

Sexually Transmitted Infections

If you smell a particularly bad odor during sex, you or your partner could have an STI like trichomoniasis, gonorrhea, or chlamydia.

• Trichomoniasis, aka trich, can cause a putrid, fishy odor from the penis or vagina. Trich can also cause itching, burning, pain while peeing or ejaculating, and abnormal yellow-green discharge.
• Chlamydia symptoms can also include burning while peeing and swelling and pain in the testicles. 
• Gonorrhea symptoms may include burning while peeing, vaginal bleeding, and painful or swollen testicles.

It’s important to note that many people with an STI present no symptoms, so keeping up with STI testing can help you ensure you or your partner don't currently have an STI causing a foul smell during sex.

Latex Condoms and Lube

Latex condoms have a distinct scent left behind after sex that often smells like rubber. Flavored condoms can also smell a bit funky or fruity. To curb these smells after sex, consider using a polyurethane-based condom.

Personal lubricants can also make sex smell different depending on its ingredients. If you have a vagina, scented lubricants may also irritate your vaginal tissue and increase your risk of vaginal infections and related foul smells.

Fecal Matter

If you're having anal sex, dealing with some feces is not abnormal. If you notice poop-related smells during or after sex, it's likely from fecal matter exiting the anus. Lingering poop particles could be on your sheets, toys, or a penis after sex.

Since the penis and vagina are also near the anus, not washing these areas can also harbor bacteria and poop odors. 

How to Make Sex Smell Better

It's normal for sex to smell due to body odors and fluids. But don't hesitate to call your healthcare provider if you're concerned about a sex-related smell or consistently smell something really foul during sex. They can screen you for infections and help treat any underlying conditions that will rid you of infection-related odors. 

Here are some other basic tips to help improve undesirable sex smells.

• Keep up your hygiene: Showering before sex and washing the genital area can help prevent stinky body odor from lingering bacteria. If you have a vagina, make sure you don't actually insert any soap into your vagina.
• Use different condoms: If you can't stand the smell of latex, consider using condoms made from materials like polyurethane.
• Avoid BV triggers: If you have a vagina and are prone to BV fishy smells, avoiding douches and scented vaginal products, using condoms and dental dams, and wearing cotton underwear may help prevent future infections.
• Practice safer sex: Using barrier methods can help you prevent STIs and their related smell. Regular screening for STIs can also help you seek treatment and avoid passing STIs to your partner(s).