Anal sex: safety and practice

The physiology that dictates the method

The internal anal sphincter is involuntary smooth muscle. It does not relax on command and it does not relax quickly. It relaxes in response to gradual, sustained pressure over time. Everything that makes anal sex comfortable follows from this, and everything that makes it painful comes from ignoring it.

The rectum is not straight — it curves at the rectosigmoid junction. Depth requires angle adjustment, not force.

The rectum does not lubricate itself.

Preparation

• Time. Ten to twenty minutes of external and shallow stimulation before any depth is not excessive; it is the method.
• Lubricant. Far more than seems necessary, reapplied repeatedly. Silicone lasts longest; use water-based with silicone toys.
• Progressive size. Finger, then two, then whatever is next. Wait at each stage for the sphincter to release rather than pushing through resistance.
• Bowel movement an hour or two beforehand is usually sufficient. Douching is optional, and frequent douching is associated with mucosal damage and higher STI rates. If douching, use low volume, lukewarm water or saline, low pressure, and not immediately before.
• Position. The receptive partner on top gives them control of depth and angle, which is why it is the standard recommendation for early attempts.

Rules that prevent injury

1. The receptive partner controls pace and depth. Always. This is a safety mechanism, not a courtesy.
2. Anything inserted must have a flared base. Rectal foreign body retrieval is a routine and entirely avoidable emergency presentation.
3. No numbing products. Pain is the feedback that prevents tearing. Anaesthetised tissue gets injured and does not report it.
4. Never anus to vagina or mouth without changing the condom, changing gloves, or washing. Gut flora in the vagina or urethra causes bacterial vaginosis and UTIs.
5. Trim nails or wear gloves. Fingernail injuries to rectal mucosa are common and invisible.
6. Stop for sharp pain or bright red bleeding. Discomfort that eases with time is normal; sharp pain is a tear signal.

Infection risk

Receptive anal intercourse carries the highest per-act HIV risk of any sexual activity — roughly 138 per 10,000 exposures from an untreated partner, against about 8 for receptive vaginal intercourse (Patel et al., 2014). Insertive anal is around 11 per 10,000, which is low but not zero.

The mechanism is mucosal fragility: the rectal lining is thin, tears easily, and sits in a bacteria-rich environment. Risk falls to effectively zero if the partner with HIV has an undetectable viral load, and by around 99 percent on PrEP taken as prescribed. Condoms plus generous lubricant reduce both HIV and bacterial STI transmission. Rectal gonorrhoea and chlamydia are common and almost always asymptomatic — a urine test does not detect them, so ask for rectal swabs.

Pegging and receptive anal for people with a prostate

The prostate is 5–7 cm in on the anterior wall. Broad, firm pressure rather than jabbing. A harness-mounted dildo lets the wearer control angle; communication about depth is the same requirement in either direction. Prostate stimulation can produce orgasm without ejaculation, and can produce a longer, more diffuse sensation than penile stimulation.

Aftercare and recovery

Some soreness for a day is normal. Warm baths help. Persistent pain, ongoing bleeding, fever, or any change in continence needs medical assessment — do not wait out of embarrassment; this is an ordinary clinical presentation.

Anal sex does not cause incontinence, and does not cause haemorrhoids, which are venous and usually related to straining. Repeated injury without healing time can cause fissures, which are painful and slow to heal. Spacing sessions matters.

Myths

• It does not "loosen" the sphincter permanently. Muscle tone returns.
• It is not exclusive to any orientation. Population surveys consistently find substantial proportions of heterosexual adults have tried it.
• It is not inherently painful. Correctly done, it should not hurt.
• Enjoying prostate stimulation says nothing about sexual orientation.

Sources

• Patel P et al. "Estimating per-act HIV transmission risk: a systematic review." AIDS, 2014.
• CDC. HIV risk estimates and STI treatment guidelines, current editions.
• Carballo-Diéguez A et al. "Rectal douching associated with receptive anal intercourse." AIDS and Behavior, 2008; Li P et al. Sexually Transmitted Infections, 2019.
• Herbenick D et al. "Sexual behavior in the United States: results from a national probability sample." Journal of Sexual Medicine, 2010.
• Stewart DB et al. "Clinical practice guideline for the management of anal fissures." Diseases of the Colon and Rectum, 2017.
• BASHH. UK national guideline on the management of anogenital infections, current edition.

Last reviewed: August 2026.