How Bad Is It Really if You Don't Pee Immediately After Sex?

So, you've just had sex. Now, you're kinda tired — or maybe just totally relaxed — do you really need to get up and go to the bathroom?

Short answer: You should.

"As a general rule, I'd say that peeing after sex is important to do," ob-gyn Taraneh Shirazian, MD, founder of Mommy Matters, tells LIVESTRONG.com.

If you're assigned female at birth (AFAB), this habit is smart for your health.

The vagina has its own unique microbiome, "a delicate equilibrium of bacteria. Anything that disrupts that can potentially create either a urinary tract infection or vagina infection thanks to new bacteria in the area," Dr. Shirazian says. "For that reason, I don't think I'm alone in encouraging someone to empty their bladder — it can only be beneficial," Dr. Shirazian says.

Here's what you need to know about the importance of peeing after sex — and how soon you need to do so.

The first reason to consider peeing after sex is a practical one: You may very well feel like you need to go.

If you are a person who has a vagina, your bladder sits right in front of your vagina, and if you're having penetrative sex, then there's a lot of pushing and pressure on your bladder. After sex, your bladder may ask to be emptied, sending you to the bathroom.

For AFAB people, your urethra — the tube that allows urine to pass through, per the National Library of Medicine (NLM) — is positioned just above your vagina. This location leaves the urethra vulnerable to new bacteria that may get introduced during sex.

When urine sits there (aka is stagnant in the bladder) and there's a new bacteria introduced, this bacteria can proliferate and lead to a urinary tract infection (UTI) in some folks, Dr. Shirazian explains. A UTI is an infection of the urinary system, most often located in the bladder and urethra, according to Mayo Clinic.

The risk of a UTI is higher if you're not using condoms and are having penetrative sex with a penis.

"There's definitely bacteria in sperm that can disrupt that balance," Dr. Shirazian says. And when we say bacteria — this is all normal bacteria and not necessarily bad. Just as the vagina has its own microbiome, so too does semen, according to a December 2021 systematic review in ​Porto Biomedical Journal​.

There's conflicting research on whether or not peeing after sex really does make a difference to preventing UTIs. One case-control study compared the behavior of premenopausal people AFAB who had recurrent UTIs and those who did not, and found that not peeing within 15 minutes of intercourse increased the risk of developing another UTI by nearly three-fold, per research in 2018 in ​Urologia Internationalis​.

In addition to peeing after, Dr. Shirazian also recommends peeing before having sex (if possible), as this means there will be less urine sitting in the bladder in the first place.

Yeast and bacterial vaginosis — an imbalance of bacteria in the vagina that often occurs when you're sexually active, according to the Centers for Disease Control and Prevention (CDC) — are both the consequences of a disruption of vaginal pH, Dr. Shirazian says.

Yeast and bacteria live in a delicate balance in the vagina — and, when in harmony, this is something you usually don't notice. Unless, well, there's a problem.

"The only time you are aware of this balance is when all of a sudden, the environment is disrupted and there's an overgrowth of yeast or bacteria," Dr. Shirazian says.

If you have penetrative sex where your partner is ejaculating inside you (or near your vagina), the sperm can disrupt the pH of your vagina. "Sperm makes vaginal pH more alkaline, which can affect the vaginal microbiome, precipitating an infection," Dr. Shirazian says.

Using condoms means that no actual sperm will mingle with your vagina, and there will be less of a risk of pH disruption — but Dr. Shirazian still advises going to the bathroom and emptying your bladder after sex anyway. Same goes for if you had penetrative sex using something other than a penis, like fingers or toys. These things can also contain bacteria that disrupts vaginal balance. This also applies to oral sex — as you know, the mouth has a lot of bacteria.

"The whole idea is that anything that introduces new bacteria in the space leaves you vulnerable. When we say things like that people think that it means it's not clean — and it's not that. Bacteria is innately on surfaces," Dr. Shirazian says.

Bacterial vaginosis (BV) and yeast infections are the two most common vaginal infections, per the CDC. Both are treatable — if you have a yeast infections you can use an over-the-counter anti-fungal treatment, such as Monistat, while for BV, your health care provider will need to first test for the infection, and then prescribe antibiotics.

If you're trying to conceive, peeing after sex will not affect sperm's ability to make their way to the fallopian tubes in search of an egg. The flip side is also true: If you're trying to prevent pregnancy, peeing after sex won't do anything — in fact, the sperm and semen will already have entered the uterus, no matter how fast you race to the bathroom, per the Cleveland Clinic.

Along with not being a birth control method, peeing after sex is also not helpful when it comes to preventing sexually transmitted infections (STIs).

While there's no need to race to the bathroom, aim to urinate fairly soon after intercourse.

The general guideline is to pee within 30 minutes, per the Cleveland Clinic. Wait longer than that, and you won't be preventing bacteria from entering the bladder, according to the Cleveland Clinic.

And feel free to go sooner: The researchers in the ​Urologia Internationalis​ study used a marker of 15 minutes when comparing UTI rates between a control group and people prone to getting these infections — not 30.

Maybe you're reading all this thinking ​I never go to the bathroom after sex, and I'm totally fine!​ That can absolutely be the case. You might not pee after sex and never get an infection. You may pee every time and still get one on occasion — or often.

"There's no way to predict what camp you'll fall into," Dr. Shirazian says. So, it's best to make this a habit, especially if you know you are prone to a vaginal infection or UTI.

Plus, if you have sex where a penis ejaculates inside your vagina, the semen will come out somehow — and for the sake of messiness, better that that fluid goes in the toilet than all over your sheets. Peeing after sex makes it easy and convenient to wash that extra fluid away — and it may also wash out bacteria that could increase your risk for UTIs or vaginal infections.

Bottom line: While a post-sex pee isn't guaranteed to prevent an infection, it's one quick step that might save you a big headache later.