Why this topic matters: Endometriosis is an oestrogen-dependent inflammatory condition in which tissue similar to endometrium grows outside the uterine cavity. It commonly causes cyclical pelvic pain, painful periods, pain during sex, bowel/bladder symptoms and infertility. Most care is planned, but emergency providers must recognise acute complications such as ruptured endometrioma, ovarian torsion, bowel or urinary obstruction, severe haemorrhage, infection, ectopic pregnancy and uncontrolled pain. Severe menstrual or pelvic pain should never be dismissed as “normal.”
Learning objectives
- Define endometriosis, describe common sites and explain inflammatory pain, adhesions and infertility.
- Take a sensitive menstrual, reproductive, pain, bowel, bladder and sexual history.
- Differentiate chronic endometriosis pain from ectopic pregnancy, torsion, appendicitis, pelvic infection and other acute abdomen emergencies.
- Perform ABCDE, pregnancy testing, focused examination, analgesia, safe referral and emergency stabilisation.
- Describe medical, hormonal, surgical, fertility, nursing and prevention-support strategies.
Definition and disease process
Endometriosis is the presence of endometrial-like glands and stroma outside the uterine cavity, commonly on the ovaries, pelvic peritoneum, uterosacral ligaments, bowel or bladder. Lesions respond to hormonal cycling, causing repeated inflammation, bleeding, fibrosis and adhesion formation. Endometriomas (“chocolate cysts”) contain old blood within the ovary.
Endometriosis is chronic and can recur. It is not cancer, but it can substantially affect education, work, relationships, sexual health, mental health and fertility. WHO notes that symptoms can be treated with medicines and, in some patients, surgery; diagnosis may use ultrasound and sometimes laparoscopy, but treatment should not be withheld simply because surgery has not yet confirmed the disease.
Common locations and clinical effects
| Location | Possible symptoms | Emergency concern |
|---|---|---|
| Ovary/endometrioma | Unilateral pelvic pain, deep dyspareunia, infertility, pelvic mass. | Torsion, rupture, haemoperitoneum or acute severe pain. |
| Pelvic peritoneum/adhesions | Cyclical pelvic pain, chronic tenderness, reduced mobility of organs. | Adhesional bowel obstruction or acute abdomen from another cause. |
| Bowel/rectum | Painful defecation, cyclical constipation/diarrhoea, rectal bleeding, bloating. | Obstruction, perforation or significant bleeding is rare but urgent. |
| Bladder/ureter | Cyclical dysuria, haematuria, flank pain or urinary frequency. | Obstruction, hydronephrosis, infection or renal injury. |
| Thorax/diaphragm (rare) | Cyclical chest/shoulder pain, breathlessness or haemoptysis. | Catamenial pneumothorax or haemothorax requires emergency assessment. |
Symptoms and impact
- Severe dysmenorrhoea, pelvic or lower-back pain that begins before menstruation and lasts through the period.
- Deep pain during or after sexual intercourse, vulvovaginal pain or fear of examination.
- Painful bowel movements, cyclical diarrhoea/constipation, bloating or blood in stool.
- Painful urination, urinary frequency or cyclical haematuria.
- Heavy or irregular bleeding, fatigue, anaemia, infertility or difficulty conceiving.
- Chronic pain sensitisation, sleep disturbance, anxiety, depression, reduced school/work attendance and relationship distress.
Emergency red flags: sudden unilateral severe pelvic pain, syncope, pallor, shock, shoulder-tip pain, positive pregnancy test, fever with guarding, persistent vomiting, abdominal distension, inability to pass urine/stool, haematuria, significant rectal/vaginal bleeding, breathlessness or haemoptysis.
First contact and compassionate communication
- Provide privacy, introduce yourself, ask the patient’s preferred name and explain every step. Severe pelvic pain is real and deserves assessment.
- Obtain consent before abdominal, pelvic, rectal or sexual-health questions/examination. Offer a chaperone and same-gender clinician when available.
- Assess ABCDE and pain severity before taking a long history. Activate emergency referral for shock, peritonism, ectopic pregnancy or torsion.
- Ask about pregnancy possibility, last menstrual period, contraception, fertility intentions, bleeding and previous endometriosis/endometrioma surgery.
- Do not assume cyclical pain is benign; do not allow a known endometriosis label to obscure a new emergency.
ABCDE assessment
A — Airway
- Assess responsiveness, vomiting, aspiration risk and need for analgesia/sedation monitoring.
- Provide airway support if shock, haemorrhage, opioid use or reduced consciousness is present.
B — Breathing
- Measure respiratory rate and SpO₂. Assess sudden breathlessness, pleuritic pain or haemoptysis for pulmonary embolism or rare thoracic endometriosis complications.
- Give oxygen for hypoxaemia or respiratory distress and arrange urgent imaging/referral.
C — Circulation
- Check pulse, BP, capillary refill, skin colour, temperature, urine output and signs of haemorrhage or sepsis.
- Establish IV access in severe pain, bleeding, shock, suspected ectopic pregnancy, torsion or sepsis; take blood for full count, group/crossmatch and chemistry.
- Give isotonic fluid for hypovolaemia under local protocol and reassess after each bolus.
D — Disability
- Record AVPU/GCS and assess collapse, severe pain, anxiety, medication effect and hypoglycaemia.
- Syncope with pelvic pain or bleeding is an ectopic-pregnancy emergency until proven otherwise.
E — Exposure
- Inspect for pallor, fever, abdominal distension, bruising, scars, vaginal bleeding and signs of infection while protecting dignity.
- Perform abdominal examination; pelvic/rectal examination requires consent, chaperone and appropriately trained staff.
Focused history
| History area | Questions | Why it matters |
|---|---|---|
| Pain | Onset, site, severity, cyclical pattern, sudden vs gradual, radiation to shoulder/back, triggers and response to medicine. | Distinguishes chronic endometriosis from torsion, rupture, ectopic, appendicitis or renal colic. |
| Menstrual | Last period, cycle, flow, clots, intermenstrual bleeding and pain before/during/after menstruation. | Assesses disease pattern, anaemia and pregnancy risk. |
| Pregnancy/fertility | Sexual activity, contraception, pregnancy intention, infertility duration and previous ectopic/miscarriage. | Pregnancy test changes urgent differential and imaging/treatment choices. |
| Bowel/bladder | Painful stool/urination, diarrhoea, constipation, rectal/urinary blood, inability to pass urine/stool. | Identifies deep disease, obstruction, infection or bleeding. |
| Previous care | Ultrasound/MRI, surgery, endometrioma, hormonal medicines, analgesics and response/side effects. | Guides safe acute treatment and specialist referral. |
| Safety/mental health | Impact on school/work, sleep, relationships, mood, coercion or sexual violence. | Chronic pain is associated with distress and requires holistic support. |
Differential diagnosis of acute pelvic pain
| Condition | Clues | Immediate action |
|---|---|---|
| Ectopic pregnancy | Positive/uncertain pregnancy, unilateral pain, bleeding, syncope, shoulder pain or shock. | Pregnancy test, IV access, resuscitation and urgent gynaecology/surgery. |
| Ovarian torsion | Sudden unilateral severe pain, vomiting, adnexal mass or intermittent attacks. | Urgent ultrasound and gynaecology; ovarian salvage is time-sensitive. |
| Ruptured endometrioma/cyst | Sudden pain, peritoneal signs, anaemia or haemoperitoneum. | Analgesia, fluids, haemoglobin/crossmatch and urgent imaging/surgical review. |
| PID/tubo-ovarian abscess | Fever, discharge, pelvic tenderness, dyspareunia or sepsis. | Pregnancy test, cultures where indicated, antibiotics and admission if severe. |
| Appendicitis/obstruction | Right lower quadrant pain, guarding, vomiting, distension or altered bowel habit. | Surgical assessment, IV fluids, analgesia and imaging. |
| Renal/urinary causes | Flank pain, haematuria, dysuria, fever or urinary retention. | Urinalysis, renal function, analgesia and obstruction/infection pathway. |
Investigations
- Urine or serum pregnancy test in every patient of reproductive potential with pelvic pain or bleeding, regardless of stated contraception.
- Full blood count for anaemia/infection, group and crossmatch when bleeding or surgery is possible, CRP, renal function, electrolytes and urinalysis.
- STI testing/swabs when discharge, pelvic tenderness or risk factors are present; test and treat sensitively.
- Pelvic ultrasound (transabdominal or transvaginal according to age, consent and local practice) to assess endometrioma, torsion, pregnancy and other pathology. NICE advises ultrasound even when examination is normal and does not recommend CA-125 as a diagnostic test.
- MRI or laparoscopy may be used by specialist teams for deep disease or uncertain diagnosis; a normal scan does not exclude endometriosis.
Immediate management of severe pain without instability
- Use a pain score and reassess after each intervention. Offer heat, positioning, privacy and calm explanation.
- Give prescribed paracetamol/acetaminophen and/or an NSAID when not pregnant and no renal disease, ulcer, anticoagulation or allergy; follow local dose limits.
- Use antiemetics for vomiting and short-course titrated opioid analgesia only when pain is severe and monitored care is available.
- Do not delay pregnancy testing or urgent imaging because analgesia was given; adequate analgesia improves examination and does not “mask” a diagnosis when reassessment continues.
- Refer for same-day gynaecology review when pain is uncontrolled, recurrent with functional impairment, associated with mass, infertility or abnormal bleeding.
Management of haemorrhage, shock or acute abdomen
- Activate emergency and surgical/gynaecology response; keep the patient nil by mouth if operative intervention is possible.
- Two IV lines where feasible, blood tests/crossmatch, isotonic crystalloid for shock, warming and repeated vital signs.
- Manage ectopic pregnancy, torsion, ruptured cyst/endometrioma, perforation or obstruction according to the specialist pathway; do not send an unstable patient for outpatient follow-up.
- Monitor haemoglobin, urine output, lactate, pain, abdominal signs and response to fluids; escalate persistent hypotension or peritonism.
Planned medical and hormonal treatment
- Analgesic plans may include NSAIDs or paracetamol, with review of effectiveness, renal/GI risk and medication overuse.
- Hormonal suppression (combined hormonal contraceptive, progestogen, levonorgestrel intrauterine system or specialist GnRH therapy) may reduce cyclical pain and bleeding; discuss contraindications, fertility goals and side effects.
- Hormonal therapy controls symptoms but does not remove all lesions. Pain may recur after stopping treatment and requires follow-up.
- Refer to a specialist endometriosis service for suspected deep disease, endometrioma, bowel/bladder/ureter involvement, persistent pain, infertility or failed first-line treatment.
Surgical and fertility considerations
- Laparoscopic excision/ablation, adhesiolysis or endometrioma surgery may be considered after shared decision-making; ovarian surgery can affect reserve and should be planned carefully.
- Discuss whether pregnancy is a current priority before hormonal suppression. Fertility referral may include expectant management, ovulation treatment or assisted reproduction depending on age, ovarian reserve and tubal/partner factors.
- Hysterectomy is not a universal cure and is considered only for selected patients who have completed childbearing and understand persistent extra-uterine pain may remain.
Nursing and EMT interventions
- Reassess pain, vital signs, bleeding, nausea, urine output and abdominal signs; document the patient’s words and functional impact.
- Provide dignity, a chaperone and trauma-informed care; avoid judgement about sexual history, fertility, menstruation or pain behaviours.
- Monitor NSAID, opioid and hormonal adverse effects; assess renal function, GI bleeding, constipation, sedation and pregnancy status.
- Support hydration, nutrition, iron evaluation when heavy bleeding is present and safe mobilisation.
- Use teach-back for warning signs: collapse, sudden one-sided pain, fever, vomiting, heavy bleeding, inability to pass urine/stool and positive pregnancy test.
- Provide written follow-up and ensure referral is not lost when symptoms are chronic or imaging is normal.
Prevention and self-management support
- Encourage a symptom/menstrual diary recording pain, bleeding, bowel/bladder symptoms, medicines, school/work impact and triggers.
- Take prescribed medicines early in the pain cycle when advised; avoid exceeding dose limits or combining duplicate NSAIDs.
- Use heat, sleep support, graded activity, pelvic-floor physiotherapy or psychological pain support when appropriate.
- Seek care early for heavy bleeding or anaemia and maintain contraception/pregnancy planning discussions.
- Remember that early recognition and respectful listening reduce diagnostic delay; there is no single blood test that excludes endometriosis.
Clinical scenarios
Scenario 1 — Sudden unilateral pain: A woman with known endometriosis develops abrupt right-sided pain, vomiting and faintness. Do not assume a routine flare. ABCDE, pregnancy test, IV access, analgesia, fluids if shocked and urgent ultrasound/gynaecology review for torsion, ectopic pregnancy or ruptured cyst.
Scenario 2 — Chronic severe dysmenorrhoea: A student misses class every month because of pain and diarrhoea. She is stable. Take a detailed menstrual/bowel history, validate the symptoms, rule out pregnancy/infection when indicated, offer safe analgesia and arrange ultrasound and gynaecology review rather than repeated emergency-only analgesia.
Scenario 3 — Deep disease: A patient has cyclical rectal bleeding, painful defecation and anaemia. Assess haemodynamic status, full blood count and stool/rectal symptoms, refer to a specialist endometriosis and colorectal pathway, and urgently investigate any heavy bleeding, obstruction or peritonism.
Common errors to avoid
- Normalising severe period pain or calling it psychological without assessment.
- Failing to perform a pregnancy test in pelvic pain or bleeding.
- Attributing sudden pain to endometriosis and missing torsion, ectopic pregnancy, appendicitis, sepsis or obstruction.
- Performing pelvic examination without consent, chaperone, explanation or trauma-informed care.
- Using CA-125 or a normal ultrasound as a reason to dismiss symptoms.
- Giving repeated analgesics without a plan for diagnosis, follow-up, fertility goals and functional impact.
PELVIC SAFE: P — Pregnancy test; E — Evaluate ABCDE and ectopic/torsion; L — Listen to pain history; V — Vital signs/bleeding; I — Investigate urine, blood and ultrasound; C — Consent/chaperone; S — Safe analgesia; A — Assess bowel/bladder; F — Fertility goals; E — Escalate red flags.
Revision questions
- Define endometriosis and explain how lesions cause cyclical pain and adhesions.
- List common bowel, bladder, reproductive and thoracic symptoms.
- Why is a pregnancy test essential in acute pelvic pain?
- Differentiate endometriosis flare, ovarian torsion, ruptured endometrioma and ectopic pregnancy.
- What consent and privacy principles apply before pelvic examination?
- Outline emergency care for the unstable patient in Scenario 1.
Key takeaways
Endometriosis pain is real, chronic and treatable—but acute pelvic pain still requires an emergency differential. Check pregnancy, assess haemorrhage and sepsis, rule out torsion/ectopic/obstruction, provide respectful analgesia and connect the patient to long-term gynaecology and fertility care.
References for further study
- WHO. Endometriosis fact sheet, updated 2025.
- NICE. Endometriosis: diagnosis and management (NG73), updated 2024.
- Royal College of Obstetricians and Gynaecologists. Endometriosis patient information.
- ACOG. Endometriosis and updated diagnosis guidance.
- Follow current Uganda Ministry of Health and specialist gynaecology protocols for acute pelvic pain, pregnancy, analgesia and surgery.