Defecation can occur during anal sex, but it can also occur during vaginal penetration or anytime you have a particularly intense orgasm.
What is the cause?
There are many reasons why this happens.
Positions during sex can put pressure on the abdomen, which may put pressure on the intestines.
Of course, just because there's pressure on your intestines (especially your lower intestine or rectum) doesn't mean you're bound to have a bowel movement.
But it can make you feel like you're going to do it.
If you don't have a chance to go to the bathroom before you start, it can accidentally make you poop—especially if you're relaxed or really in the moment.
You may have heard that some people poop during labor.
Well, the same thing happens with an intense orgasm during vaginal intercourse.
This is because orgasm causes the uterus to contract, just like during labor, causing stool to slip out.
When you orgasm, hormonal compounds called prostaglandins are released. These cause the uterus to contract and increase blood flow to the lower pelvis to help with lubrication.
This extra lubrication can sometimes make it harder to control your poop (or pee).
Anal sex can give a person the urge to have a bowel movement.
Part of the reason is that there are so many nerve endings in this part of the body.
When your internal anal sphincter relaxes (like when you go to the bathroom), you may think that's what you're about to do.
And even if you're not engaging in anal play, sexual arousal increases blood flow to the anal tissue.
This makes the anal canal moist, making it easier for poop to slide out.
That said, it's worth noting that pooping during anal sex is still fairly rare. It's more likely that you just have a little fecal material transfer, which is NBD.
Nerve damage or injury to the anal sphincter can increase the chance of having a bowel movement during sex.
These types of injuries can be caused by constipation, sustained force during childbirth, or during sexual assault.
Nerve damage can also be the result of certain diseases, including multiple sclerosis, inflammatory bowel disease, and diabetes.
Hemorrhoids or rectocele can also cause anal leakage.
Should you see a doctor?
If this only happens once - especially after an intense orgasm - then you probably don't need to worry.
But if it happens frequently or you're worried about it, it's best to talk to your doctor or other health care provider.
They can help you determine whether it is related to an underlying condition and advise you on next steps.
What can you do to help prevent this?
The best thing you can do is go to the bathroom to empty your bowels before getting busy.
The less waste there is in the colon, the less likely it is to be passed out during sex.
Of course, this is easier to do if you have a regular bowel habit. Drinking more water, eating fiber-rich foods, and exercising can all help you maintain a more regular schedule.
If you're worried about pooping during anal sex, you can always give yourself an enema. Kits are usually available at local pharmacies.
What would you do if it happened to you?
First, try to stay calm. Yes, you may feel embarrassed, but if you panic or react impulsively, it may cause you to say or do something you regret later.
Next, if you're comfortable doing so, consider telling your partner what just happened.
That way, they'll know why you need to stop and clean up, and won't think you're alienating them or kicking them out because of something they did.
This can help alleviate any shame or embarrassment you may feel.
It may also help reduce anxiety about it happening again because the two of you can make plans.
What should you do if this happens to your partner?
If this happens to your partner, try not to panic or react in a way that might make them feel bad about the situation.
Yes, this may not be what you expected to happen, but if you react poorly, it may make your partner withdraw or feel ashamed, which may have long-term effects on your relationship.
Perhaps develop a plan by discussing prepared stances and steps for how to help prevent this situation next time.
If they don't want to talk about it, that's okay. Just let them know you'll support them if they change their mind.
Sex can be messy. In some cases, this means unexpected poops.
If it does occur, consider discussing it with your partner or your doctor to help relieve anxiety or other unwanted feelings.
This can help you better prepare for your next sexual encounter and maximize your chances of things going as planned.