Pain during sex that starts out of nowhere, after months or years of comfortable intercourse, almost always has a physical explanation. The medical term is secondary dyspareunia, meaning pain that develops after a period of pain-free sex. The causes range from simple (a new medication drying out vaginal tissue) to complex (endometriosis or pelvic floor muscle spasms), but most are treatable once identified.
Where the pain shows up and when it happens during sex are the two biggest clues to what’s going on.
Pain at Entry vs. Deep Pain
Painful sex generally falls into two categories, and they point to different problems. Entry pain, sometimes called superficial dyspareunia, is felt at the vaginal opening during initial penetration. It’s more commonly tied to dryness, skin irritation, infections, or involuntary muscle tightening. Deep pain happens with full penetration and tends to worsen in certain positions. It’s more closely linked to conditions affecting the uterus, bowel, bladder, or the ligaments holding pelvic organs in place.
Knowing which type you’re experiencing helps narrow the list of possible causes considerably.
Vaginal Dryness and Hormonal Shifts
Insufficient lubrication is the single most common reason sex becomes painful. Sometimes the fix is as straightforward as more foreplay or using a lubricant. But when dryness is new and persistent, hormones are often behind it.
Estrogen keeps vaginal tissue thick, elastic, and naturally moist. When estrogen drops, that tissue becomes thinner, drier, and more fragile. It also changes the acid balance of the vagina, making infections more likely. This happens most dramatically during and after menopause, but it also occurs during breastfeeding, after childbirth, and in the years leading up to menopause when hormone levels start fluctuating.
Several common medications can also dry things out by suppressing arousal or lubrication: antidepressants, blood pressure medications, antihistamines, sedatives, and certain birth control pills. If your pain started around the time you began a new prescription, that connection is worth investigating.
Infections and Skin Conditions
Yeast infections, bacterial vaginosis, urinary tract infections, and sexually transmitted infections all cause inflammation that makes penetration painful. The pain typically comes on relatively fast and is often accompanied by other symptoms like unusual discharge, itching, burning during urination, or odor. Pelvic inflammatory disease, a more serious infection that spreads to the uterus and fallopian tubes, can cause deeper pain along with fever and pelvic tenderness.
Skin conditions affecting the vulva or vaginal opening, including eczema and other forms of dermatitis, create chronic irritation that makes contact painful. These are easy to overlook because people don’t always connect a skin issue with sexual pain.
Pelvic Floor Muscle Tension
Your pelvic floor is a group of muscles that stretches like a hammock across the bottom of your pelvis. When these muscles are stuck in a state of constant contraction, a condition called hypertonic pelvic floor, they can’t relax enough to allow comfortable penetration. The result is a tight, burning, or sharp pain, usually at the vaginal entrance but sometimes deeper.
Stress is a major trigger. Pelvic floor muscles tend to tighten in response to life stress, sometimes without you realizing it. Past injuries, surgeries, childbirth, and chronic pain conditions can also train these muscles to stay clenched. The tricky part is that pain itself reinforces the pattern: you anticipate pain, the muscles tighten, penetration hurts, and the cycle continues.
Vaginismus is a related condition where the vaginal muscles involuntarily spasm during attempted penetration. The leading theory is that a fear of painful sex triggers the muscles to clamp down automatically, creating a self-reinforcing loop of fear, tightening, and pain. This can develop even in people who previously had comfortable sex, especially after a painful experience, a difficult medical exam, or a period of heightened anxiety.
Endometriosis and Other Pelvic Conditions
Endometriosis is one of the more common causes of deep pain during sex. It occurs when tissue similar to the uterine lining grows outside the uterus, often on the fallopian tubes, ovaries, or the tissue lining the pelvis. These misplaced growths produce their own estrogen, which fuels local inflammation in a feedback loop. In more advanced cases, the growths invade the peritoneum or pelvic organs and create adhesions, essentially scar tissue that glues organs together. When those organs are pushed or shifted during deep penetration, it hurts.
Other conditions that cause deep pain include ovarian cysts, uterine fibroids, a retroverted (tilted) uterus, uterine prolapse, and adenomyosis (where the uterine lining grows into the muscular wall of the uterus). Bowel conditions like irritable bowel syndrome and bladder conditions like interstitial cystitis can also make deep penetration painful because of how closely these organs sit next to the vaginal canal.
After Surgery or Childbirth
Scarring from pelvic surgery, including hysterectomy, can change the internal landscape enough to cause pain where there wasn’t any before. Episiotomies (surgical cuts made during delivery to widen the birth canal) and perineal tearing during childbirth can leave scar tissue at the vaginal opening that remains sensitive for months or longer. Cancer treatments, particularly radiation and chemotherapy targeting the pelvic area, cause tissue changes that frequently make sex painful.
Painful Sex in Men
This isn’t exclusively a problem for people with vaginas. Men can experience sudden painful sex too, most often from prostatitis, which is inflammation or infection of the prostate gland. Symptoms include pain during or after ejaculation, pelvic pain, and sometimes difficulty with erections. Acute bacterial prostatitis comes on suddenly with fever and signs of infection. Chronic pelvic pain syndrome is a longer-lasting version that may stem from urinary or sexually transmitted infections, pelvic floor muscle tightness, or other factors. Risk factors include diabetes, immunosuppression, prostate enlargement, and recent catheter use.
Tight foreskin, infections of the penis or urethra, and Peyronie’s disease (scar tissue inside the penis causing curvature) are other causes worth considering.
How the Cause Gets Identified
A medical evaluation typically starts with a detailed history: when the pain began, exactly where it hurts, whether it happens in every position or with every partner, and what it feels like (burning, aching, sharp, pressure). Your surgical history, childbirth history, and sexual history all factor in.
A pelvic exam lets a clinician check for visible signs of irritation, infection, or structural changes. They may apply gentle pressure to different areas of the genitals and pelvic muscles to locate the source of pain. A speculum exam allows a visual inspection of the vaginal walls. If conditions like endometriosis, cysts, or fibroids are suspected, a pelvic ultrasound can help confirm what’s going on internally.
What Treatment Looks Like
Treatment depends entirely on the cause, which is why getting an accurate diagnosis matters more than trying to push through the pain. Infections are treated with the appropriate medication. Hormonal dryness often responds well to topical estrogen or over-the-counter lubricants and moisturizers. Medication-related dryness may resolve with a dosage change or a switch to a different prescription.
For pelvic floor dysfunction and vaginismus, pelvic floor physical therapy is one of the most effective approaches. A specialist works with you on exercises and techniques to retrain the muscles to relax. Sessions may include biofeedback, which uses sensors to show you how your muscles are responding in real time, helping you learn to release tension you didn’t know you were holding. Treatment plans often include lifestyle changes and home exercises alongside in-office sessions.
Endometriosis and structural conditions like fibroids or cysts may require hormonal management or, in some cases, surgical intervention depending on severity. The key point is that none of these conditions improve by being ignored, and many of them worsen over time without treatment. Pain during sex is not something you need to accept as normal, regardless of your age or how long it’s been happening.