Symptom · Endometriosis & adenomyosis in perimenopause
The pain you were told was normal was not normal.
The full guide to both conditions. Endometriosis affects roughly 1 in 10 women; adenomyosis, its close sibling growing inside the wall of the uterus, affects up to 1 in 5. Both take years to diagnose and neither politely retires at menopause. The broad picture: what's happening, how they behave in the 40s when estrogen swings get bigger, what HRT decisions look like with a history of either, and why hysterectomy is only sometimes the end of it. If you want the day-to-day tracker for adenomyosis specifically (bleeding volume, clots, cramping), there's a companion page for that.
Educational · not medical advice
Endometriosis is when tissue similar to the lining of the uterus grows outside it, most often on the ovaries, fallopian tubes, bowel, bladder and pelvic wall. Adenomyosis is the same kind of rogue endometrial-like tissue, but inside the muscular wall of the uterus itself, turning the uterus heavy, boggy and painful. They're sister conditions: same tissue logic, different location, and up to a third of people with one have the other. Every cycle that tissue responds to estrogen, builds, and tries to shed. The result: inflammation, scar tissue, severe period pain, pain with sex, bowel and bladder symptoms, fatigue and fertility issues. Neither is 'a bad period'. Both are chronic, systemic, estrogen-driven inflammatory diseases, and two of the most under-diagnosed conditions in women's health. The 'finally diagnosed at 45' story is so common it should be a meme. Perimenopause is often when the symptoms get loud enough, or the imaging clear enough, that someone finally listens.
Why this is happening now
Endo and adeno are hormonal, immune and neurological at the same time. Knowing the moving parts, and where they differ, helps decisions later.
- 01
Endo grows outside the uterus, adeno grows inside its wall
Endometriosis lesions are most often on the ovaries (where they form chocolate cysts called endometriomas), the pelvic peritoneum, the bowel, the bladder, and the ligaments holding the uterus. Adenomyosis is the same kind of tissue burrowed into the muscular wall of the uterus itself, making it enlarged, boggy and painful. Same tissue logic, different address, which is why the experience overlaps so heavily and the two often co-exist.
- 02
Both are inflammatory diseases, not just 'painful periods'
Endo and adeno lesions secrete inflammatory cytokines and prostaglandins, recruit immune cells, and create chronic local inflammation that drives pain, adhesions and central sensitization over time. This is why fatigue, brain fog, gut issues and full-body pain are part of the picture for many women, it isn't only a pelvic problem.
- 03
Diagnosis is still slow and imperfect
Average diagnostic delay is 7 to 10 years for endo. Ultrasound and MRI can detect endometriomas, deep infiltrating endo, and adenomyosis (which has fairly characteristic imaging features, bulky uterus, junctional zone thickening, cysts in the muscle wall) but routinely miss superficial peritoneal endo. The historical gold standard for endo is laparoscopy with biopsy; adeno is increasingly diagnosable on a good MRI. A normal scan does not rule either out.
- 04
In perimenopause it usually gets worse before it gets better
Estrogen swings in perimenopause are bigger and more erratic than in the 30s, and bigger surges feed both endo and adeno. Many women describe theirs getting worse in their 40s: heavier bleeding, longer pain windows, more bowel involvement, a uterus that feels heavier and crampier than it used to. This is the rule, not the exception.
- 05
Neither always stops at menopause
Both are estrogen-driven, so for many women symptoms ease when periods stop. But not all. Fat tissue continues to make estrogen after menopause. Adhesions, scar tissue and nerve damage built up over decades don't disappear with the last period. And women on HRT can see disease activity restart, sometimes mildly, sometimes significantly. Post-menopausal endo and adeno are real and under-recognized.
- 06
Hysterectomy: curative for adeno, not always for endo
This is the biggest practical difference between the two. Adenomyosis lives in the uterine wall, so removing the uterus removes the disease, hysterectomy is genuinely curative for adeno. Endometriosis lesions live outside the uterus, so they remain after a hysterectomy unless they're also excised. 'I had a hysterectomy and the pain came back' is the classic endo story. For endo, excision of all visible disease by a specialist surgeon is what changes long-term outcomes, not the hysterectomy itself.
What tends to help
There is no single fix. The combination, hormonal suppression, expert excision when needed, pain modulation, gut and nervous-system care, is what moves the needle.
See an endo/adeno specialist, not just a general gynecologist
Outcomes for endo surgery vary enormously by surgeon experience. Look for an accredited endometriosis centre or a surgeon doing high-volume excision (not ablation). Adeno is more often managed medically or with hysterectomy, but a specialist can also offer uterine-sparing options like adenomyomectomy or uterine artery embolization if you're not done with the uterus yet. For complex disease, bowel, bladder, deep infiltrating endo, severe adeno, this is the single most important decision you'll make.
Hormonal suppression to stop the cycle
Continuous combined pill, the hormonal IUD (Mirena, particularly effective for adeno), progestin-only options (norethindrone, dienogest) and GnRH analogues all aim to stop the monthly proliferation that fuels both conditions. Each has trade-offs and they don't work equally for everyone, but for many women they buy years of better quality of life.
Excision surgery, not ablation, when endo surgery is on the table
For endo: excision (cutting the lesion out) has substantially better long-term outcomes than ablation (burning the surface). If a surgeon is recommending ablation, ask why and consider a second opinion at a specialist centre. For adeno, the surgical conversation is different, usually hysterectomy if you're done with the uterus, or uterine-sparing options (adenomyomectomy, embolization) if you're not.
Pelvic-floor physiotherapy
Years of pain create chronic pelvic-floor tightness, painful sex, bladder urgency and constipation, true for both conditions. A pelvic-floor physio trained in persistent pain is one of the most under-prescribed game-changers in endo and adeno care. Internal work matters; ask for it.
4 more practices, plus podcasts, books and research, live in Go deeper below.
03When to get help nowWhen this needs more than self-care
Emergency red flags, same-week signs, and where to find a menopause-trained practitioner.
When this needs more than self-care
6 more signs it needs a doctor this week
Period pain that stops your life, even once a month
Pain that means missing work or school, vomiting, taking strong painkillers, or curling up unable to function is not normal period pain. Push for a referral to a gynecologist with endo and adeno experience, not just a scan, not just the pill.
Pain with sex, with bowel movements, or with urination
All three are classic endo signs and all three are routinely missed because doctors or specialists don't ask. Bring them up explicitly. They point to deep or organ-involving disease and change the urgency of investigation.
Fertility difficulty
Endometriosis is found in roughly 30 to 50% of women with infertility, and adenomyosis carries its own fertility implications (implantation issues, higher miscarriage risk). If you're struggling to conceive and have any of the above symptoms, ask for an endo- and adeno-aware fertility workup, not a generic one.
Heavy bleeding with worsening pain in your 40s
Common in perimenopause, and easy to dismiss as 'just perimenopause'. With a known or suspected history of endo or adeno, it's worth a specialist look. The combination of heavy clotty bleeding plus a heavy crampy uterus is the textbook adeno picture, and it's routinely written off as 'your age'.
Symptoms continuing or returning after menopause
Pelvic pain, bowel symptoms, or pain with sex after menopause is not 'in your head' and is not always genitourinary syndrome of menopause (GSM). Post-menopausal endo, residual lesions, adhesions, retained adeno tissue and HRT-reactivated disease are all real. A menopause-aware gynecologist is the right door.
You have endo or adeno and HRT is being suggested without a specialist conversation
HRT can be the right call with either history, but the choice of regimen matters. If a doctor or specialist is suggesting estrogen-only HRT post-hysterectomy without acknowledging endo history, that's a flag to get a second opinion from a menopause specialist who knows endo.
Go deeper
One place for everything else.
Practices to try this week, voices worth hearing, books worth your bedside table, rooms where members are talking, the candid tips Nila would share over a cup of tea, and the research the editorial team is watching.
Pain, when, where, how bad, what it stops you doing
Date, severity (1 to 10), location (pelvis / lower back / bowel / bladder / leg / a heavy crampy uterus), and what it cost you that day (work, sex, exercise, sleep). Two months of this is more useful in a clinic appointment than ten minutes of trying to remember.
Cycle phase
Endo and adeno pain are classically worst in the days before and during bleeding, but in perimenopause and in deep infiltrating disease (or severe adeno) it can be daily. Knowing whether your pain is cyclical, daily, or 'cyclical layered on top of daily' changes treatment.
Bowel and bladder symptoms tied to your cycle
Cyclical diarrhoea, constipation, blood in stool or urine around your period, painful bowel movements, urinary urgency that worsens with bleeding, these are flags for bowel or bladder endometriosis and warrant a specialist scan.
Bleeding, volume, clots, how long, how often
Heavy, prolonged, clot-filled bleeding and short cycles are classic adenomyosis flags (and often the loudest signal in perimenopause). Track pad/tampon changes, flooding, clots bigger than a 50p / quarter, and how many days you bleed. This is the kind of evidence that gets you taken seriously and onto the right scan.
Pain with sex, depth and timing
Deep dyspareunia (pain on deep penetration) often points to deep infiltrating endo, adhesions or pelvic-floor involvement. Worth tracking specifically: many women stop having sex rather than reporting it, and doctors or specialists don't ask.
Fatigue and brain fog around your cycle
Endo- and adeno-related fatigue is real and is now in the literature as a recognized symptom, not just 'the pain is exhausting'. Tracking it as a separate symptom helps make the case for treating these conditions systemically, not just locally.