Ectopic Pregnancy

Implantation of a fertilized ovum outside the uterine cavity — most commonly in the fallopian tube (>95%, predominantly ampullary), less commonly ovarian, cervical, cesarean scar, or abdominal. Cannot proceed to viable pregnancy and carries risk of tubal rupture causing life-threatening intra-abdominal hemorrhage — leading cause of first-trimester maternal mortality.

Risk factors: prior ectopic pregnancy (strongest), prior tubal surgery/damage, pelvic inflammatory disease/prior salpingitis (chlamydia particularly implicated), IUD in situ, assisted reproduction, smoking, prior pelvic/abdominal surgery.

• Classic triad (not always all present): amenorrhea/missed period, abdominal/pelvic pain, vaginal bleeding — presentation highly variable, maintain high suspicion in any woman of reproductive age with abdominal pain
• Pain: typically unilateral lower abdominal/pelvic, but can be diffuse; shoulder tip pain indicates diaphragmatic irritation from hemoperitoneum — significant red flag
• Vaginal bleeding: typically light/dark, though can be absent or mimic normal menstruation
• Signs of tubal rupture (surgical emergency): severe sudden-onset abdominal pain, hypovolemic shock (may be disproportionate to visible vaginal blood loss since bleeding is intraperitoneal), peritonism, shoulder tip pain, syncope/collapse
• Examination: abdominal tenderness, cervical excitation/adnexal tenderness on bimanual exam (perform gently — some protocols avoid bimanual exam if ectopic strongly suspected pending ultrasound), adnexal mass may be palpable
• Any hemodynamically unstable woman of reproductive age with abdominal pain — assume ruptured ectopic until excluded

• Urine/serum beta-hCG: mandatory first test in any reproductive-age woman with abdominal pain or abnormal bleeding — positive result with no confirmed intrauterine pregnancy requires ectopic to be actively excluded
• Transvaginal ultrasound: investigation of choice — absence of intrauterine gestational sac with positive beta-hCG above the discriminatory zone (typically ~1500-2000 IU/L) raises strong suspicion; may directly visualize adnexal mass, free fluid in pouch of Douglas
• Pregnancy of unknown location (PUL): beta-hCG positive but no pregnancy visualized — requires serial beta-hCG monitoring (normal early intrauterine pregnancy typically rises ≥53-66% every 48 hours; ectopic/non-viable typically shows suboptimal rise, plateau, or fall) with repeat ultrasound
• FBC, group and save/crossmatch (essential given hemorrhage risk), clotting profile if significant bleeding suspected

Differentials: miscarriage, ovarian cyst rupture/hemorrhage, ovarian torsion, pelvic inflammatory disease, appendicitis, corpus luteum cyst, urinary tract pathology.

Hemodynamically unstable (suspected ruptured ectopic — surgical emergency):

• Immediate resuscitation: large-bore IV access, aggressive crystalloid, urgent crossmatched blood, activate major hemorrhage protocol
• Emergency laparoscopy (or laparotomy if patient too unstable) — do not delay for extensive imaging; salpingectomy typically performed if significant damage/hemorrhage, salpingostomy considered in selected stable cases with desire for future fertility and healthy contralateral tube
• Anti-D prophylaxis if Rh-negative

Hemodynamically stable:

Expectant management: for very early, small, low and falling beta-hCG (typically <1000-1500 IU/L and falling), asymptomatic, with close monitoring — many resolve spontaneously.

Medical management (methotrexate): for hemodynamically stable, minimal symptoms, unruptured ectopic, no fetal cardiac activity, beta-hCG typically <5000 IU/L, adnexal mass <35mm, no significant free fluid, and able to comply with follow-up

• Methotrexate 50mg/m² IM single dose
• Contraindications: hemodynamic instability, ruptured ectopic, breastfeeding, immunodeficiency, significant hepatic/renal/hematologic impairment, coexisting intrauterine pregnancy
• Monitoring: serial beta-hCG on days 4 and 7 (expect ≥15% decline between day 4-7), then weekly until negative — may initially rise before falling; repeat dose if inadequate decline; counsel on avoiding NSAIDs, alcohol, sun exposure and folic acid supplements during treatment; advise against conception for typically 3 months

Surgical management (laparoscopic salpingectomy or salpingostomy): for stable patients not suitable for or declining other options (larger mass, higher beta-hCG, visible fetal cardiac activity, patient preference) — laparoscopic preferred over laparotomy in stable patients.

Anti-D prophylaxis: to all Rh-negative women undergoing surgical management; per local protocol for medical/expectant management.

Follow-up: serial beta-hCG until confirmed negative regardless of approach (detects persistent trophoblastic tissue), counseling on future pregnancy risk (recurrence ~10-15% after one ectopic) and early ultrasound in future pregnancies, psychological support.

Referral: gynecology for all suspected ectopic — same-day assessment; immediate theatre activation for any hemodynamically unstable presentation.