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Endometriosis

A chronic, estrogen-fueled inflammatory disease where tissue resembling the uterine lining grows outside the uterus, affecting roughly 1 in 10 women of reproductive age, with an average diagnostic delay of about 7 years1.

Hormonal & Women's Health Evidence-Based

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Definition

What Is Endometriosis?

Endometriosis is a systemic, chronic inflammatory disease in which endometrial-like tissue (glands and stroma resembling the uterine lining) implants and grows outside the uterus, most commonly on the ovaries, fallopian tubes, pelvic peritoneum, bladder and bowel.

Unlike normal uterine lining, these lesions have no exit route. Each cycle they respond to estrogen by proliferating, bleeding internally and triggering a cascade of inflammation, scar tissue and adhesions that fuse pelvic organs. The disease is now understood as inflammatory and immune-driven, not merely "misplaced tissue"; local estrogen synthesis by the lesions themselves keeps them growing even when systemic estrogen is normal.

The standard staging system, from the American Society for Reproductive Medicine, divides endometriosis into 4 stages based on lesion location, depth and adhesion burden. Stage does not predict pain (a Stage I patient may have severe pain while a Stage IV patient may have minimal pain), but it does predict fertility impact and surgical complexity2:

The uterus, fallopian tubes and ovaries within the pelvis, with red patches of endometriosis lesions on the uterus and pelvis, a dark endometrioma on one ovary and bands of adhesions
💡 Key Insight: Endometriosis is a chronic, estrogen-dependent, inflammatory disease affecting approximately 10% of reproductive-aged women3, with diagnosis delayed by about 7 years from symptom onset on average.4

Stage I, Minimal (most commonly missed)

A few superficial peritoneal implants, less than 5 mm deep, with no or minimal adhesions. Often dismissed on laparoscopy as "unremarkable," yet pain and inflammation can be severe.

  • โ†’Hallmarks: Cyclical pelvic pain, often without any visible ultrasound finding
  • โ†’Primary lever: Specialist assessment and hormonal treatment, with anti-inflammatory eating for pain56
  • โ†’Imaging: Usually normal; diagnosis often requires laparoscopy

Stage II, Mild

More implants, some deeper (greater than 5 mm), and a few filmy adhesions appearing on the ovaries or cul-de-sac. Pain typically increases and dyspareunia (painful intercourse) becomes common.

  • โ†’Hallmarks: Cyclical pain + deep dyspareunia + premenstrual bowel symptoms
  • โ†’Primary lever: Specialist assessment and hormonal treatment, with anti-inflammatory eating for pain5
  • โ†’Imaging: May still appear normal on standard ultrasound

Stage III, Moderate

Multiple deep implants plus one or more ovarian endometriomas (chocolate cysts), with denser adhesions in the pelvis. Fertility becomes measurably impacted. Bowel, bladder and chronic fatigue symptoms are common.

  • โ†’Hallmarks: Endometriomas on ultrasound, dyschezia (painful bowel movements), subfertility
  • โ†’Primary lever: Specialist referral, with excision surgery for endometriomas where needed5
  • โ†’Imaging: Endometriomas visible on transvaginal ultrasound, possibly on MRI

Stage IV, Severe

Deep infiltrating endometriosis (DIE) with large endometriomas, dense adhesions and often a "frozen pelvis" where bowel, bladder, ureters and reproductive organs fuse. Significant fertility impact and often debilitating chronic pain.

  • โ†’Hallmarks: Severe pain, infertility, bowel/​bladder involvement, fatigue
  • โ†’Primary lever: A specialist endometriosis service, with surgery and pain management planned together
  • โ†’Imaging: MRI usually shows DIE, kissing ovaries, bowel involvement
By the Numbers

Endometriosis by the Numbers

~1 in 10
women of reproductive age worldwide have endometriosis, about 190 million people7
6.7 years
average delay from first symptoms to a surgical diagnosis, across 16 centers in ten countries4
4 to 12 years
the range of average delays to diagnosis reported worldwide, which is why pain that stops daily life deserves assessment rather than reassurance7
25 to 50%
of women with infertility have endometriosis, on WHO's estimate7
40 to 50%
estimated recurrence within 5 years of surgery, and about 21.5% at 2 years, in a review of published series8
51%
the share of the risk explained by genes, on a twin study's estimate; endometriosis runs in families9
Signs & Symptoms

Symptoms of Endometriosis

Endometriosis is famously a "great mimic." It can wear the costume of IBS, interstitial cystitis, chronic fatigue, fibromyalgia or depression. A common thread is pain that worsens around periods, though pelvic pain can also continue between them7.

SymptomWhat happens
Reproductive & Pelvic Pain Symptoms
Severe Dysmenorrhea (Disabling Period Pain)Pain that prevents work, school or daily activity, requires bed rest or fails to respond fully to standard NSAIDs. Often begins in adolescence and is wrongly normalized for years.
Deep Dyspareunia (Painful Intercourse)Sharp, deep pain with penetration or specific positions, often persisting for hours or days after sex. Caused by direct contact with lesions in the cul-de-sac, uterosacral ligaments or rectovaginal septum.
Heavy or Prolonged Bleeding (Menorrhagia)Soaking a pad or tampon every 1 to 2 hours, large clots, periods lasting more than 7 days and bleeding through to bedding or clothing. Often paired with iron deficiency, fatigue and dizziness.
Infertility / SubfertilityWHO estimates that as many as 25 to 50% of women with infertility have endometriosis7. Mechanisms include adhesions distorting tubes and ovaries, inflammation impairing egg quality and altered uterine receptivity to implantation.
Low Back, Hip & Sciatica-Like PainCyclical low back ache, deep hip pain and shooting leg pain (especially with bowel movements during menses) suggest lesions on the uterosacral ligaments or sciatic nerve.
GI, Bladder & Systemic Symptoms
Dyschezia & Cyclical Bowel SymptomsPainful bowel movements during menses, alternating constipation and diarrhea synchronized with the cycle, rectal bleeding during periods and bloating so severe many call it "endo belly."
Bladder Pain & Urinary UrgencyBurning with urination during menses, increased frequency, urgency, suprapubic pressure and (rarely) cyclical hematuria.
Chronic Fatigue & Brain FogDeep, immovable fatigue out of proportion to sleep, plus difficulty concentrating, word-finding problems and poor memory. Chronic pain, disturbed sleep and iron loss from heavy bleeding all contribute, and iron deficiency is worth testing for directly rather than assuming.
Anxiety, Depression & Pain CatastrophizingEndometriosis can affect mental health, including depression and anxiety, and years of dismissed pain add to it7. Central sensitization can amplify pain signals long after lesions are addressed.
Nausea, Vomiting & Fainting With MensesSevere nausea, vomiting, diarrhea, sweating and even fainting at the height of menstrual pain. If you faint or feel faint, or the pain is sudden and severe, get emergency care10.
โš ๏ธ Pattern to watch for: Disabling cyclical pain + bowel/​bladder symptoms that worsen with menses + painful intercourse is a strong reason to be assessed for endometriosis, even before imaging.
Causes

Causes of Endometriosis

The causes of endometriosis are unknown; these are the factors with the most evidence behind them7.

CauseHow It Contributes to EndometriosisWhat Helps
Retrograde menstruationSome tissue shed during a period flows back through the fallopian tubes into the pelvis; this is thought to be the most likely cause, though no one knows for sure11Hormonal treatment such as a combined oral contraceptive or a progestin, which NICE advises offering for suspected or confirmed endometriosis12
Hormonal cycling and estrogenPatches of endometriosis break down and bleed with each cycle but cannot leave the body, and estrogen appears to promote the disease11Hormonal treatment from your doctor, and acetaminophen or an NSAID for pain12; no diet has been shown to remove lesions or change the stage6
Family history and genesEndometriosis runs in families, and a twin study estimated that genes explain about half the risk9Tell your doctor if a mother, sister or aunt has it; they will ask, and it is a reason to seek assessment early13
The immune systemEndometriosis is associated with immune dysregulation, and people with it have higher rates of lupus, multiple sclerosis and inflammatory bowel disease7Care for any coexisting condition in its own right; persistent pain after surgery often reflects one14
Menstrual patternPeriods lasting more than 7 days, cycles of 27 days or fewer, never having had children, or anything that blocks menstrual flow make it more likely11A pain and bleeding diary for your doctor, and treatment of heavy periods, which can cause iron deficiency and fatigue7
Diet, as an association onlyIn observational studies, more trans fat and less omega-⁠3 are linked with a higher risk of endometriosis; this is an association, not proof of cause6The diet section's pattern: fewer trans fats and ultra-processed foods, and fatty fish 2 to 3 times a week
Diagnosis

How Endometriosis Is Diagnosed

Definitive diagnosis still requires laparoscopy with biopsy, but careful clinical evaluation, expert imaging and supportive labs can build a strong working diagnosis well before surgery. Symptoms alone, in a typical pattern, are reason to begin treatment.

TestWhat it shows
At-Home Screening
These are not diagnostic on their own, but strong patterns warrant a referral to an endometriosis-literate provider:
Cyclical Symptom & Pain DiaryTrack at least 3 cycles, logging pain location, intensity (0 to 10), bowel and bladder symptoms, dyspareunia, fatigue and bleeding. A clear premenstrual and menstrual flare across multiple systems is the most diagnostic single screening tool. Symptom-tracking apps are useful, but a simple notebook works.
NSAID Response & Trigger TrackingNote whether ibuprofen taken at full dose (400 to 600 mg) prior to pain onset gives meaningful relief. Pain that acetaminophen or an NSAID does not control is a reason for further assessment and referral12. Also track flares triggered by dairy, gluten, alcohol or stress; this gives a useful baseline before starting elimination work.
Lab & Clinical Tests
Transvaginal & Pelvic Ultrasound (Expert Operator)A normal scan does not rule endometriosis out12. A specialist deep-endometriosis TVUS by a trained sonographer can detect endometriomas, deep infiltrating disease, bowel and bladder involvement, and ovarian fixation ("kissing ovaries"). Specifically request "DIE protocol" ultrasound when available.
Pelvic MRI (with Endometriosis Protocol)Best non-invasive imaging for deep infiltrating endometriosis and surgical planning. Identifies endometriomas, rectovaginal disease, bladder lesions and adhesions. Order specifically as "MRI pelvis with endometriosis protocol," not generic pelvic MRI; the read changes meaningfully.
Hormone PanelEstradiol, progesterone (day 21) and FSH/LH can help rule out other hormonal causes of symptoms. Blood hormone levels do not diagnose endometriosis, and urine estrogen metabolite tests are not validated for it.
Inflammation & Iron Panelhs-CRP, ESR, CA-⁠125 (which should not be used to diagnose endometriosis), ferritin, iron, TIBC, transferrin saturation and CBC. Iron deficiency from heavy bleeding is common and worsens fatigue; fix it aggressively.
Diagnostic Laparoscopy (Gold Standard)Still the definitive test when imaging is inconclusive. Excision is generally preferred for deep disease5, so ask the surgeon which approach they plan and why. Biopsy confirms diagnosis histologically.
Treatment Comparison

Conventional and Holistic Treatment for Endometriosis

๐ŸŒฟ HOLISTIC
๐Ÿ’Š CONVENTIONAL
๐ŸŒฟ

Holistic / Functional Approach

Ease pain and other symptoms with diet, pelvic floor physical therapy and pain management, alongside medical care

Primary Treatment
Anti-inflammatory diet and pelvic floor physical therapy, alongside medical care; in small trials, fish oil, vitamin D, curcumin and resveratrol did no better than placebo for pain15
Duration
3 to 6 months to judge whether pain improves; no diet has been shown to produce remission6
Effect on Underlying Disease
Can ease pain and inflammation; no dietary intervention has been shown to remove lesions or alter disease stage6
Fertility Outcome
Diet has not been shown to change fertility; many women conceive without help and others need assisted reproduction2

Full Holistic Approach Includes

  • Anti-inflammatory whole-food eating: if you suspect gluten or dairy, remove it for a 90-⁠day trial and then reintroduce it (replace the calcium if you remove dairy), minimize alcohol, prioritize omega-⁠3 rich foods
  • Fiber-rich nutrition: cruciferous vegetables daily, ground flax 1 to 2 tbsp/day, soluble fiber
  • Supplements only after discussing them with your doctor; the supplement table sets out what each trial found
  • Pelvic floor physical therapy for hypertonic pelvic floor (common in endometriosis14)
  • Castor oil packs over the lower abdomen if you find them soothing; there is no evidence they affect lymphatic drainage or the disease
  • Pain management: physical therapy and cognitive behavioral therapy can reduce pain and improve quality of life7; yoga and relaxation if they help you
  • Gut health: fermented foods, fiber, a wide variety of plant foods
  • Expert excision surgery referral when needed, coordinated with pre- and post-op nutrition
โš ๏ธ Side effects: Gas or bloating as fiber increases, and stomach upset from some supplements.
Supplement Protocol

Evidence-Based Supplements for Endometriosis

Supplements do not treat endometriosis, and several below did no better than placebo in trials. The list below sets out what has been tried and what the trials found, with nutrients that heavy bleeding can deplete.

Supplement What it is for Typical range Timing Notes & cautions
Omega-⁠3 EPA/DHA (Fish Oil)The most-studied anti-inflammatory supplement for endometriosis. In a placebo-controlled trial in young women with endometriosis, fish oil did not reduce pain more than placebo17. Trial evidence in endometriosis itself is small and mixed6.Not recommended for endometriosis pain (the trial used 1,000 mg a day)Not applicableEat fatty fish such as wild salmon or sardines instead. If you are pregnant or trying to conceive, check with your midwife or doctor before taking fish oil. In heart trials, fish oil supplements raised the risk of atrial fibrillation, an irregular heartbeat, more so above 1 g a day18, so check any fish oil supplement with your clinician first. At higher doses fish oil can increase bleeding risk; tell your clinician if you take a blood thinner or have heavy bleeding.
Curcumin (Turmeric Extract)In a placebo-controlled trial of 68 women with endometriosis, 1,000 mg a day for 8 weeks did not reduce pain or improve quality of life19.Not recommended for endometriosis pain (the trial used 1,000 mg a day)Not applicableTurmeric supplements may be unsafe in pregnancy20.
Vitamin D3 (with K2)In a placebo-controlled trial in young women with endometriosis, vitamin D reduced pain no more than placebo17.D3: not shown to ease endometriosis pain (the trial used 2,000 IU a day); if you take it for other reasons, set the dose with your clinician; most adults need no blood test first; K2 (MK-⁠7): 100 to 200 mcg per dayWith a fat-containing meal, morning preferredIf you take warfarin, clear any vitamin K supplement with the clinician managing your anticoagulation before starting or stopping it: vitamin K antagonizes warfarin, and changing your intake destabilizes the INR. Consistency matters more than avoidance. This does not apply in the same way to direct oral anticoagulants such as apixaban or rivaroxaban, but tell your prescriber about any supplement you take.
Magnesium GlycinateMay help sleep; evidence in endometriosis is lacking.300 to 600 mg elemental magnesium per dayEvening, 30 to 60 min before bed; add an extra 100 to 200 mg during mensesCitrate also works but can loosen stools. The upper intake level for supplemental magnesium is 350 mg a day; the top of this range is above it, as is any extra during menses. Above it diarrhea is common, so agree on the dose with your clinician (your midwife or doctor if you are pregnant or trying to conceive). With kidney disease, take it only on your clinician's advice.
ZincWorth correcting if your intake is low; evidence in endometriosis is lacking.15 to 30 mg per dayWith meals (food prevents nausea)If using long-term at higher doses, add 1 to 2 mg copper to prevent imbalance.
ResveratrolIn a randomized trial, adding resveratrol to a combined oral contraceptive did not reduce endometriosis pain more than placebo21.Not recommended for endometriosis pain (the trial used 40 mg a day)Not applicableCheck with your midwife or doctor first if you are pregnant or trying to conceive.
B-ComplexA general B vitamin supplement; no benefit for endometriosis has been shown.1 capsule per day per product labelMorning with foodIf trying to conceive, ensure 400 to 800 mcg folic acid a day, the form shown to prevent neural tube defects22.
Iron (if deficient)Heavy menstrual bleeding routinely depletes iron and worsens fatigue, brain fog and pain tolerance. Replete aggressively when ferritin is low.Per labs, often 25 to 65 mg elemental iron 3x/weekEmpty stomach with vitamin C, or per providerBisglycinate (gentle iron) is best tolerated. Retest ferritin every 8 to 12 weeks. The top of this range sits above the 45 mg/day tolerable upper intake level for adults. That is appropriate only when correcting a confirmed deficiency under clinical supervision, not as general supplementation. Test ferritin first, and retest rather than staying on it indefinitely.
Ginger Root ExtractIn a trial of 150 students with ordinary period pain, pain eased over three days on ginger 250 mg four times a day; there was no placebo group, and ginger has not been tested in endometriosis23.250 mg 3 to 4x per day during mensesStart 2 days before expected menses, continue through day 3Capsules, tea or fresh root. Ginger supplements may be safe in pregnancy; check with your midwife or doctor first24.
French Maritime Pine Bark ExtractIn a small study of 58 women after surgery, pine bark extract slowly reduced symptom scores over 48 weeks, less than a GnRH agonist but without suppressing periods25. Anti-inflammatory and antioxidant.30 to 60 mg 2x per dayWith mealsThe study used 60 mg a day; the top of this range is double that, so set the dose with your clinician. Check with your midwife or doctor first if you are pregnant or trying to conceive.
What to Expect

What to Expect Over Time

No existing treatment removes endometriosis for good; treatment aims to control symptoms and limit long-term effects7.

Treatment and supportive care, together
First Weeks

A doctor asks about symptoms and family history and may examine you and arrange an ultrasound; a normal scan does not rule endometriosis out12. Start a pain and bleeding diary.

Months 1 to 3

NICE advises a trial of about 3 months of acetaminophen or an NSAID, and offering hormonal treatment such as a combined oral contraceptive or a progestin; if pain is not controlled, further assessment and referral follow12. Diet changes, such as a trial without gluten, can be tested with reintroduction16.

Months 3 to 12

If treatment does not help or the disease is extensive, surgery can remove lesions, cysts and adhesions; physical therapy and cognitive behavioral therapy can reduce pain7.

Long Term

Symptoms can return after treatment or surgery, with recurrence estimated at 40 to 50% within 5 years of surgery8. Symptoms usually stop after menopause13. Raise fertility plans early2.

When to Seek Care

Call 911 or go to the emergency department for sudden, severe pelvic pain, pelvic pain with a fever or chills, feeling faint or fainting, or pelvic pain with heavy bleeding10. Get a same-day appointment for heavy bleeding, soaking a pad or tampon every hour for more than 2 hours; call 911 if it comes with dizziness, fainting, chest pain or breathlessness. See a doctor promptly if period pain stops your normal activities, or symptoms affect daily life, work or relationships13.

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Next Steps

Disabling Period Pain Deserves Assessment

Period pain that stops your normal activities deserves assessment, not reassurance. Hormonal treatment and pain relief come from your doctor, and anti-inflammatory eating may ease symptoms for some. No diet has been shown to remove lesions or change the stage.

Explore Ovarian Cysts โ†’ Explore IBS & IBD โ†’

References & Evidence Notes

Each numbered entry below is either a source you can follow or a note setting out what the evidence does and does not support. Both are numbered together so the markers in the text line up.

Last reviewed October 20, 2026. Supplement entries are cross-checked against the NIH National Center for Complementary and Integrative Health and the Linus Pauling Institute Micronutrient Information Center.26 Two things this page cannot do. It cannot diagnose endometriosis, which needs a specialist and usually laparoscopy, and it cannot remove lesions. What it can do is help with pain and other symptoms alongside medical care; no diet has been shown to remove lesions, and several supplements did no better than placebo in trials. If you have severe period pain that stops you from functioning, pain during sex, or pain with bowel movements or urination during your period, push for a referral rather than accepting that periods are meant to hurt. The average delay to diagnosis is about 7 years. Endometriosis is also a recognized cause of infertility, so if you are trying to conceive, raise it early.

  1. On diagnostic delay: delays of around seven years from symptom onset are consistently reported, 6.7 years on average in a ten-country study (note 4). Contributors include normalization of severe menstrual pain, symptom overlap with irritable bowel syndrome and imaging that is often normal in superficial disease. Laparoscopy with histology remains the definitive diagnosis, though guidelines increasingly support empirical treatment before it. ↩
  2. On fertility: endometriosis is associated with reduced fertility through distorted anatomy, inflammation and effects on oocyte quality. Many women conceive without help; others need assisted reproduction. Surgery before IVF is decided case by case. This is a conversation to have early rather than after a year of trying. ↩
  3. On what it is: endometrial-like tissue outside the uterus, responsive to hormonal cycling, producing inflammation, adhesions and pain. It affects roughly 10% of women of reproductive age, PubMed 42355752. Lesion burden correlates poorly with pain severity, which is one reason stage I disease can be more painful than stage IV and why dismissing minimal disease is a clinical error. ↩
  4. On diagnostic delay: in 1,418 women having laparoscopy at 16 centers in ten countries, the delay between symptom onset and a surgical diagnosis of endometriosis averaged 6.7 years, longer where care was mainly state-funded (8.3 against 5.5 years), PubMed 21718982. ↩
  5. On treatment: hormonal suppression (combined contraceptives, progestins, GnRH analogs with add-back) reduces pain for many, and excision or ablation surgery is used for disease not responding to medical management, with excision generally preferred for deep disease. Recurrence after surgery is common. Multidisciplinary pain management matters because central sensitization persists after lesions are treated. ↩
  6. On diet: observational studies associate higher omega-⁠3 and lower trans fat intake with lower endometriosis risk, and small trials of anti-inflammatory dietary patterns report symptom improvement. No dietary intervention has been shown to remove lesions or alter disease stage. Treat diet as pain and symptom management, which is a real contribution, not as treatment of the disease. ↩
  7. On the disease, its causes and its treatment: the World Health Organization estimates that endometriosis affects about 10% (190 million) of reproductive-age women worldwide, that the average time to diagnosis is 4 to 12 years, and that as many as 25 to 50% of women with infertility have it. Its causes are unknown; it is associated with immune dysregulation and with higher rates of lupus, multiple sclerosis and inflammatory bowel disease. There is no cure: treatment aims to control symptoms, with pain relief, hormonal medicines, surgery that can remove lesions, adhesions and scar tissue, fertility treatment, and physical therapy and cognitive behavioral therapy for pain. Lesions and symptoms can recur, and heavy bleeding can cause iron deficiency and fatigue, WHO, endometriosis fact sheet. ↩
  8. On recurrence: a review of published series estimated recurrence after surgery for endometriosis at 21.5% at 2 years and 40 to 50% at 5 years, and found the evidence for medication after surgery scanty, PubMed 19279046. ↩
  9. On genes: a twin study estimated the heritability of endometriosis at 51%, and genetic studies since have identified many risk variants, PubMed 42695929. ↩
  10. On emergencies: NHS guidance advises calling emergency services or going to the emergency department for pelvic pain that is severe, getting worse or hurts to move or touch; for pelvic pain with feeling faint, dizzy or light-headed, or passing out; for pelvic pain with heavy vaginal bleeding; and, where pelvic infection is possible, for sharp, sudden and intense lower abdominal pain or a very high temperature or feeling hot, cold or shivery, NHS, pelvic pain, NHS, pelvic inflammatory disease. ↩
  11. On possible causes: the US Office on Women's Health states that no one knows for sure what causes endometriosis; that backward (retrograde) menstrual flow is the most likely cause; that it runs in families; that immune problems, estrogen and abdominal surgery may play a part; and that it is more likely with periods lasting more than seven days, cycles of 27 days or fewer, never having had children, or a condition that blocks menstrual flow, Office on Women's Health, endometriosis. ↩
  12. On diagnosis and first treatment: the NICE guideline advises a short trial, for example 3 months, of acetaminophen or an NSAID for endometriosis pain, with further assessment and referral if it does not help; offering hormonal treatment such as combined birth control pills or a progestin for suspected, confirmed or recurrent endometriosis; not excluding endometriosis when the examination and ultrasound are normal; and not using the blood test CA-⁠125 to diagnose it, NICE NG73, endometriosis. ↩
  13. On symptoms and care: NHS guidance lists severe period pain that stops normal activities, heavy periods, pelvic and back pain, pain on passing stool or urine, pain during or after sex, fatigue and difficulty getting pregnant. It advises seeing a doctor if symptoms affect everyday life, work or relationships, notes that the doctor will ask about close relatives with endometriosis, that laparoscopy can confirm it, that surgery can remove areas of endometriosis or cysts, and that symptoms usually stop after menopause, NHS, endometriosis. ↩
  14. On coexisting conditions: adenomyosis, interstitial cystitis, pelvic floor dysfunction, irritable bowel syndrome and fibromyalgia coexist with endometriosis at higher-than-chance rates. Persistent pain after adequate surgery often reflects one of these rather than recurrence, and treating the wrong one is a common source of years lost. ↩
  15. On supplement trials in endometriosis: in placebo-controlled trials, vitamin D and fish oil in 69 young women, curcumin in 68 women and resveratrol added to a combined oral contraceptive in 44 women did not reduce pain more than placebo; all were small, PubMed 32453393, PubMed 37818734, PubMed 29264492. ↩
  16. On gluten-free diet and endometriosis pain: in a retrospective study of 207 women with severe endometriosis-related pain and no control group, 75% reported a significant change in pain after 12 months gluten-free, PubMed 23334113. ↩
  17. On vitamin D and fish oil: in a randomized, placebo-controlled trial of 69 young women aged 12 to 25 with endometriosis, 2,000 IU of vitamin D3 or 1,000 mg of fish oil a day for 6 months did not reduce pain significantly more than placebo, PubMed 32453393. ↩
  18. Gencer B, Djousse L, Al-Ramady OT, Cook NR, Manson JE, Albert CM. Effect of long-term marine omega-⁠3 fatty acids supplementation on the risk of atrial fibrillation in randomized controlled trials of cardiovascular outcomes: a systematic review and meta-analysis. Circulation. 2021;144(25):1981-⁠1990. PubMed 34612056. Seven trials with 81,210 people followed for about 5 years: omega-⁠3 supplements were linked to a higher risk of atrial fibrillation (hazard ratio 1.25), more so in trials of more than 1 g a day (1.49), and the risk rose with each additional gram. ↩
  19. On curcumin: in a randomized, placebo-controlled trial of 68 women with endometriosis, 500 mg of curcumin twice a day for 8 weeks did not reduce pain or improve quality of life, PubMed 37818734. ↩
  20. On turmeric in pregnancy: the NIH's complementary health center states that the use of turmeric supplements during pregnancy may be unsafe, NCCIH, turmeric. ↩
  21. On resveratrol: in a randomized trial of 44 women with endometriosis taking a combined oral contraceptive, adding 40 mg of resveratrol a day for 42 days reduced pain no more than placebo, PubMed 29264492. ↩
  22. On which form of folate: folic acid is the only form of folate shown to help prevent neural tube defects, and people with MTHFR variants can process it, CDC, MTHFR Gene Variants and Folic Acid. ↩
  23. On ginger and period pain: in a trial of 150 students with primary dysmenorrhea, pain eased over three days in women taking ginger 250 mg four times a day, in a trial with no placebo group; women with endometriosis were not studied, PubMed 19216660. ↩
  24. On ginger in pregnancy: the NIH's complementary health center states that ginger supplements may be safe in pregnancy and advises discussing any herbal product with a health care provider first, NCCIH, ginger. ↩
  25. On pine bark extract: in a study of 58 women after conservative surgery for endometriosis, 60 mg a day for 48 weeks slowly reduced symptom scores, less efficiently than a GnRH agonist but without affecting menstrual cycles, PubMed 17879831. ↩
  26. National Center for Complementary and Integrative Health (NIH), nccih.nih.gov, and the Linus Pauling Institute Micronutrient Information Center, lpi.oregonstate.edu/mic. ↩