Clinical overview
This chapter is the operational complement to acute-pelvic-pain-pathophysiology. There you learn why pelvic pain hurts. Here you learn what to do when she walks through the door at 02:00 on a Saturday with severe lower abdominal pain. Acute pelvic pain in a woman of reproductive age is a high-stakes presentation: an unrecognised ruptured ectopic, a missed torsion, or a delayed tubo-ovarian abscess all carry serious morbidity, and three of those are routinely missed because the clinician anchored on a benign diagnosis early.
A safe approach is a parallel resuscitation–assessment–diagnosis pathway. You do not move sequentially from history to examination to investigation to disposition; you do all four simultaneously, with re-evaluation at fixed intervals. The single most important triage question is "is this patient haemodynamically stable?" — because the answer drives whether she goes to a CT scanner or straight to theatre.
The chapter is organised the way the consultation actually flows: initial triage (ABCDE), focused history, focused examination, prioritised investigations, working differential, definitive disposition, follow-up. We then drill into the three high-risk diagnoses you cannot miss: ectopic pregnancy, ovarian torsion, and tubo-ovarian abscess.
Core knowledge
Triage and primary survey
Resuscitate first. ABCDE.
- Airway and breathing: usually unremarkable unless septic.
- Circulation: tachycardia, narrow pulse pressure, cool peripheries, delayed capillary refill, low or postural blood pressure. Two large-bore cannulae. Blood for FBC, U&E, CRP, group-and-save (cross-match 2 units if any haemodynamic concern), lactate, blood culture if febrile.
- Disability: GCS, glucose.
- Exposure: temperature, full abdominal exposure, look for surgical scars and signs of self-harm or trauma.
A pregnant or pregnancy-possible woman in shock without obvious external bleeding is a ruptured ectopic until proven otherwise. Do not wait for ultrasound; alert theatre and resuscitate with crystalloid and group-specific blood while you confirm.
Assessment
Focused history
Ten minutes, structured. The non-negotiable items:
- Onset, character, radiation, severity, time course — already discussed in acute-pelvic-pain-pathophysiology. Has the pain changed in character (dull → sharp) suggesting peritoneal involvement?
- Last menstrual period; cycle regularity; possibility of pregnancy. Always assume pregnancy is possible until β-hCG returns. Sexual activity, partners, condom use, contraception (and exact contraception type — a Mirena dramatically shifts your differential).
- Associated symptoms: bleeding (amount, clots, products), discharge (colour, odour), nausea/vomiting, fever, dysuria, bowel symptoms, shoulder-tip pain.
- Past gynaecological history: prior STIs, prior PID, prior ectopic, fertility treatment, fibroids known, endometriosis known, ovarian cysts known, recent gynaecological procedures (TOP, hysteroscopy, IUD insertion).
- Obstetric history: parity, prior caesarean (consider scar ectopic), recent delivery (consider postpartum endometritis or ovarian vein thrombosis).
- Past medical and surgical: appendicectomy done?, IBD, prior pelvic surgery, anticoagulants, immunosuppression.
- Allergies, drug history, social (smoking, alcohol, recreational drugs, partner abuse — see gender-based-violence).
- HIV status and current ART regimen if positive — see hiv-counselling. PID in immunocompromised patients runs a more aggressive course.
Focused examination
- General: pallor, sweating, restlessness, distress level (cannot lie still suggests colic; lying very still suggests peritonism).
- Vitals: full set, including temperature; capillary refill; postural BP if stable enough.
- Abdomen: inspect (scars, distension, masses), palpate (start away from the pain, work towards it; document guarding, rebound, percussion tenderness), auscultate (absent bowel sounds → ileus; tinkling → obstruction).
- Pelvis:
- Inspection: vulval lesions, bleeding, products at the os.
- Speculum: cervical bleeding, discharge, products, cervix open or closed, identify the os.
- Bimanual: cervical motion tenderness, uterine size and tenderness, adnexal masses and tenderness, fullness in the pouch of Douglas.
- Rectovaginal exam when posterior masses or uterosacral nodularity suspected.
Always offer a chaperone; document who was present.
Investigations — sequenced by priority
Within 5 minutes:
- Urine β-hCG (or serum if recent intercourse and very early).
- Bedside glucose, lactate (point-of-care if septic).
Within 30 minutes:
- FBC, U&E, CRP, LFTs (consider if right-sided pain), coagulation if any bleeding, group-and-save / cross-match.
- Endocervical swabs (chlamydia, gonorrhoea, M. genitalium — PCR).
- High vaginal swab for bacterial vaginosis / candida if discharge.
- Urinalysis ± culture.
Within 60 minutes:
- Transvaginal ultrasound is the imaging investigation of choice for the gynaecologist. It answers four questions in one study: (1) is there an intrauterine pregnancy? (2) is there free fluid? (3) is there an adnexal mass? (4) is there an obvious uterine cause (degenerating fibroid, haemometra)?
- Consider transabdominal ultrasound additionally for large pelvic masses extending out of the pelvis.
- CT abdomen-pelvis if non-gynaecological cause suspected (appendicitis, diverticulitis, urolithiasis, bowel obstruction). Never delay theatre for a CT in a shocked patient.
β-hCG interpretation in early pregnancy:
- Positive β-hCG + intrauterine pregnancy visualised on TVS = likely intrauterine pregnancy (but heterotopic still possible after ART — see ectopic-pathophysiology).
- Positive β-hCG + no IUP visualised + β-hCG ≥1500 IU/L (discriminatory zone, lower in some units) = ectopic until proven otherwise.
- Positive β-hCG + no IUP + β-hCG <1500 = "pregnancy of unknown location" (PUL); repeat β-hCG in 48 h. A normal IUP doubles in 48 h; a failing pregnancy halves; an ectopic typically plateaus.
Building the working differential
Use the patient's pregnancy status and haemodynamic stability to triage:
Pregnant and unstable: ruptured ectopic, ruptured corpus luteum cyst with significant bleed, very rarely a uterine rupture in early pregnancy (uncommon).
Pregnant and stable: ectopic (intact or with small leak), miscarriage (threatened, inevitable, incomplete, septic), corpus luteum cyst, ovarian torsion (more common in early pregnancy because of ovarian enlargement), heterotopic if ART.
Not pregnant and unstable: ruptured ovarian cyst with significant haemoperitoneum (especially endometrioma rupture), severe sepsis from tubo-ovarian abscess, ovarian vein thrombosis with sepsis.
Not pregnant and stable, premenopausal: PID (most common), ovarian torsion, ovarian cyst with rupture or haemorrhage, endometriosis flare, degenerating fibroid, primary dysmenorrhoea, mittelschmerz.
Not pregnant and stable, postmenopausal: rule out malignancy. Any postmenopausal "cyst" is a mass; CA-125, RMI calculation, urgent gynae-oncology MDT review. See ultrasound-malignancy-signs.
Non-gynaecological always to consider: appendicitis, mesenteric adenitis, urolithiasis, UTI, pyelonephritis, diverticulitis, IBD flare, hernia, musculoskeletal pain, herpes zoster (pre-rash phase).
Management
Three diagnoses you cannot miss
1. Ruptured ectopic pregnancy
Tubal ectopic pregnancy with rupture and pelvic internal bleeding.
A woman of reproductive age, abdominal pain, positive β-hCG, no IUP, and haemodynamic instability → straight to theatre. Do not wait for repeat β-hCG. Do not wait for transabdominal ultrasound. Alert theatre, alert the consultant, alert the anaesthetist, alert the blood bank.
Resuscitate with crystalloid (1–2 L), then blood products. Permissive hypotension to a systolic of 80–90 mmHg until haemorrhage is controlled — over-resuscitation worsens dilutional coagulopathy.
Surgical management: laparoscopic salpingectomy is the standard if the contralateral tube is healthy. Laparoscopic salpingostomy is acceptable if the contralateral tube is absent/diseased and the patient wants future fertility; counsel that persistent trophoblast may need methotrexate.
Anti-D 250 IU IM for Rhesus-negative women (lower dose because the gestation is early; check local policy). See rh-isoimmunisation.
Full clinical management is detailed in ectopic-pregnancy-management.
2. Ovarian torsion
A young woman with sudden severe unilateral iliac fossa pain, nausea and vomiting out of proportion to pain, and an enlarged ovary on ultrasound (even with apparently preserved Doppler) → theatre. The "wait and see" approach loses the ovary.
Laparoscopy: detort the ovary, do NOT do a salpingo-oophorectomy on the apparently dusky organ. Studies (Oelsner, Bider, Bouguizane) consistently show that even a black, oedematous, "necrotic-looking" ovary recovers in the majority once perfusion is restored. Reassess at second-look laparoscopy at 6 weeks if function uncertain.
Address the underlying cyst (cystectomy of a benign dermoid or simple cyst, with frozen section if any suspicion of malignancy). In a child or adolescent with normal ovaries that have torted (so-called "normal-ovary torsion") consider oophoropexy with non-absorbable suture from the utero-ovarian ligament to the round ligament, but evidence base is modest.
3. Tubo-ovarian abscess (TOA)
A woman with severe bilateral lower abdominal pain, fever, raised inflammatory markers, and an adnexal mass on ultrasound — with or without a history of recent PID. Admission, IV antibiotics covering chlamydia, gonorrhoea, anaerobes, and Gram-negatives. South African NDoH STG regimen: ceftriaxone 1 g IV daily + metronidazole 500 mg IV 8-hourly + doxycycline 100 mg PO 12-hourly. Continue IV until afebrile and CRP falling for 48 hours, then convert to oral to complete 14 days.
Drainage: percutaneous (image-guided) drainage is first-line for unilocular abscesses ≥6 cm or those failing 48–72 hours of IV antibiotics. Surgical drainage (laparoscopic) for multiloculated or inaccessible abscesses, or for ruptured TOA with peritonitis (which is a surgical emergency).
Partner treatment and contact tracing are mandatory. HIV testing offered. Repeat ultrasound at 2 weeks to confirm resolution.
Pain control
Underused. Properly written analgesia is part of safe care, not "masking the picture" — modern practice is that adequate analgesia does not obscure surgical signs.
- Paracetamol 1 g IV/PO 6-hourly.
- NSAIDs (ibuprofen, diclofenac, ketorolac) — exclude pregnancy first, caution in renal impairment.
- Tramadol 50–100 mg PO 6-hourly for moderate pain in the non-pregnant patient.
- Morphine titrated IV in 2 mg aliquots for severe pain; ensure antiemetic.
- Avoid opioids in early pregnancy if possible; if needed, use the lowest effective dose.
- Antispasmodics (hyoscine butylbromide 20 mg IV) for crampy pain.
Document pain scores at presentation and after analgesia.
Disposition
- Theatre: shocked patient with positive β-hCG (suspected ruptured ectopic), suspected torsion, suspected ruptured TOA with peritonitis, suspected uterine perforation post-instrumentation.
- Admit to ward: PID requiring IV antibiotics, stable ectopic on medical management (some units admit, others outpatient — local protocol), TOA on antibiotics, severe ovarian cyst rupture with significant haemoperitoneum but stable, incomplete miscarriage awaiting surgical evacuation.
- Discharge with follow-up: confirmed ruptured corpus luteum cyst, mild PID on outpatient regimen, mittelschmerz, simple cyst rupture without significant bleeding.
Refer for early follow-up: 48-hour ward review or early pregnancy unit re-assessment if PUL; gynae-oncology MDT if postmenopausal mass; sexual health for partner notification in PID.
Red flags / pitfalls
- Anchoring on PID. A woman with a positive β-hCG and pelvic pain has an ectopic until proven otherwise — never PID. Resist the urge to start antibiotics and watch.
- Reassurance from a normal Doppler in suspected torsion. Take the patient to theatre.
- Missing the second pregnancy. Heterotopic pregnancy after ART is uncommon but real; an IUP on ultrasound is not protective.
- Sending home a postmenopausal woman with a "simple cyst." No cyst is simple after menopause; she gets imaging, tumour markers, and an MDT slot.
- Failure to repeat β-hCG. A single low β-hCG with no IUP is not a diagnosis — it is the start of one. Repeat at 48 h.
- Anti-D omission. Any bleeding or surgical intervention in a Rhesus-negative pregnant woman requires anti-D. Check local dose schedule.
- Inadequate analgesia. Pain control is humane and improves cooperation with examination and imaging.
- Not testing for HIV. SA practice mandates offer in any acute gynaecological presentation, especially if STI suspected. Co-infection alters management of PID and surgical risk.
- Not arranging follow-up for "discharged with reassurance" patients. A 48-hour phone or in-person review catches the small minority whose diagnosis evolves.
- Ignoring the patient's own concern. A woman saying "this is worse than my last delivery" or "something is very wrong" is reporting a clinically important sign — listen.
Evidence anchors
- RCOG Green-top Guideline No. 21 — Management of Tubal Pregnancy (2016, latest revision).
- RCOG Green-top Guideline No. 32 — Management of Acute Pelvic Inflammatory Disease.
- ACOG Practice Bulletin No. 174 — Evaluation and Management of Adnexal Masses (2016, reaffirmed).
- ACOG Practice Bulletin No. 193 — Tubal Ectopic Pregnancy.
- NICE NG126 — Ectopic Pregnancy and Miscarriage: Diagnosis and Initial Management (2019).
- BASHH 2018 UK National Guideline for the Management of Pelvic Inflammatory Disease.
- South African National Department of Health Standard Treatment Guidelines and Essential Medicines List (Hospital level, latest edition) — PID and ectopic protocols.
- South African National HIV Guidelines (2023) — relevance for HIV co-infected presentations.
- Oelsner G, Shashar D. Adnexal torsion. Clin Obstet Gynecol 2006 — landmark on ovarian preservation post-detorsion.
- Royal College of Radiologists iRefer guidelines — imaging algorithms for acute pelvic pain.