Synopsis
Triage sudden pelvic pain safely, exclude pregnancy-related and time-critical surgical causes, and use focused examination, testing and imaging to reach a defensible working diagnosis.
- Start with physiology and pregnancy status: instability overrides the diagnostic sequence, while every person with pregnancy potential should be offered prompt urine or serum hCG even when contraception was used or the history seems atypical.
- Separate pregnancy-related causes, gynaecological causes and non-gynaecological causes, then prioritise by harm: ectopic pregnancy, torsion, haemorrhagic cyst, pelvic infection, appendicitis, urinary obstruction and bowel disease can overlap clinically.
- Pain character helps but does not decide the diagnosis: abrupt maximal pain supports torsion, rupture or colic; progressive bilateral pain with discharge supports infection; cyclical pain suggests endometriosis but an acute complication can coexist.
- Use consented abdominal examination and, when it will change care, speculum and bimanual examination; severe pain, trauma history or inability to tolerate examination should lead to modification or deferral, not coercion.
- Transvaginal ultrasound is usually the most informative pelvic imaging test when acceptable, but early ectopic pregnancy, torsion and superficial endometriosis may remain occult; interpret imaging alongside trajectory and examination.
- Do not postpone empirical treatment of clinically suspected pelvic inflammatory disease while awaiting swabs, because delayed treatment increases risks of chronic pain, ectopic pregnancy and infertility.
- A pregnancy of unknown location is a temporary classification and could still be ectopic: symptoms override hCG results, obtain 2 serum hCG measurements as near as possible to 48 hours apart but not earlier, then arrange the trajectory-specific clinical review, ultrasound or urine-test follow-up with written 24-hour safety-netting.
- Reassess after analgesia and initial tests; worsening pain, new observations, falling haemoglobin or diagnostic discordance should trigger escalation and repeat senior examination rather than discharge by a normal single result.
Key red flags
Hypotension, tachycardia, pallor, collapse, guarding or rebound tenderness indicates haemorrhage, sepsis or visceral perforation until proved otherwise and requires immediate senior review.
A positive pregnancy test with abdominal, pelvic or cervical-motion tenderness needs immediate early-pregnancy or out-of-hours gynaecology assessment because ectopic pregnancy remains possible at any hCG concentration.
Sudden unilateral pain with nausea or vomiting raises adnexal torsion; preserved Doppler flow or transient improvement does not safely exclude intermittent or partial torsion.
Fever, purulent discharge, marked pelvic tenderness or a suspected tubo-ovarian abscess suggests complicated pelvic inflammatory disease and may require admission, intravenous antibiotics and drainage.
Postmenopausal pain, a persistent or complex mass, unexplained weight loss, ascites or early satiety requires malignancy assessment rather than repeated symptomatic treatment.
Investigation priorities
Identify pregnancy-related risk and establish a baseline when pregnancy location is uncertain.
Management branches
Observations, perfusion or examination suggests shock, major internal bleeding, peritonitis or severe sepsis.
- Run ABCDE, summon senior gynaecology, anaesthesia and the relevant surgical team, obtain large-bore access and activate local emergency protocols.
- Send pregnancy testing, blood count, coagulation, renal profile, lactate and crossmatch while giving analgesia, warmed fluid or blood products according to physiology.
- Use focused bedside imaging only if it changes the immediate route; do not delay theatre or interventional treatment for comprehensive imaging in a deteriorating patient.