Ejaculation is typically associated with pleasure and relief. But for some men, it is followed by an unexpected and uncomfortable pain in the buttocks, pelvis, or lower back. This experience is more common than many admit, yet it is rarely discussed openly—often leaving men confused, anxious, and silent.

So why does this happen?

Ejaculation is not a simple release. It is a complex physiological process involving the pelvic floor muscles, nerves, prostate gland, and lower spine. When any of these systems is strained, inflamed, or dysfunctional, pain can occur immediately after climax.v

One of the most frequent causes is pelvic floor muscle tension. During ejaculation, these muscles contract forcefully. If they are already tight—due to prolonged sitting, stress, or physical inactivity—they may spasm and send pain signals to the buttocks. This is increasingly common among men with sedentary lifestyles or desk-based work.

Another significant cause is prostatitis, an inflammation of the prostate gland. The prostate plays a key role in ejaculation, and when inflamed or infected, it can cause pain that radiates to the buttocks, perineum, or lower back. Men with prostatitis may also experience burning during urination, pelvic heaviness, or pain during ejaculation.

Nerve irritation is also a factor. The pudendal and sciatic nerves, which run through the pelvis and buttocks, are deeply involved in sexual function. Prolonged sitting, spinal problems, or muscle compression can irritate these nerves, leading to sharp or aching buttock pain after ejaculation—especially when sitting or bending

In some cases, the pain is referred from the lower back or sacroiliac joint. Ejaculation involves intense muscular contractions, which can aggravate existing spinal or joint issues, causing pain to be felt in the buttocks rather than the back itself.

Psychological stress should not be overlooked. Chronic stress and anxiety can cause persistent pelvic muscle tension. Over time, this tension can make ejaculation painful even when no infection or structural problem is present.

While occasional discomfort may not be alarming, persistent or recurring pain after ejaculation is not normal. Men should seek medical attention—preferably from a urologist—if the pain continues, worsens, or is accompanied by symptoms such as fever, urinary pain, or blood in semen or urine. Diagnosis may involve physical examination, laboratory tests, or imaging, and treatment can include medication, pelvic physiotherapy, posture correction, or stress management.