Ectopic pregnancy

Section: Emergency Curriculum: Curriculum, page 29

Definition

• Implantation of fertilized embryo in an extra-uterine location

Epidemiology

• 2% of all pregnancies
• Higher risk in older, multigravid women

Pathophysiology

• Fertilisation with abnormal implantation
• Commonest site is the fallopian tube
  • Other sites include the ovary, cervix, abdominal, caesarian scar (rare)
• Blood supply drawn from implantation site but these alternative sites do not have the ability to accommodate the growth → rupture
• Sac rupture between 6 and 16 weeks which leads to big bleed

Aetiology

• Risk factors
  • Tubal damage - PID, tubal ligation, prev abdo surgery
• Previous ectopic
• Smoking
• Multiple sexual partners
• Advanced maternal age

• 2 years of infertility

Clinical

• Triad - lower abdominal pain, amenorrhea and post vaginal bleeding
• Other signs of pregnancy - breast tenderness, fatigue, nausea
• With rupture - shock, rigid abdomen

Investigations

• Serum hCH and FBC
  • Usually rises by ⅔ every 2 days but this rise is less with ectopics
• Pelvic USS
  • Normal gestational sac visible at 3 weeks post conception
  • If an intrauterine sac is seen with or without fetal cardiac activity - can exclude ectopic
• Free fluid if haemoperitoneum/retrograde menstruation

Diagnosis

• Made with pelvic USS demonstrating absence of an intrauterine sac
• Any concerns can be correlated with serial hCG
• Differential Diagnosis
  • GIT - hollow viscous perforation, appendicitis, diverticulitis

Management

Expectant

• Can be done if asymptomatic, well and need to correlate with falling hCG

Medical

• Methotrexate - 1 off IM injection
  • Antimetabolite chemotherapy which binds dihydrofolate reductase
  • Acts on trophoblastic tissue

Surgical

• Indications
  • Haemodynamic instability
  • Symptoms
• Options
  • Laparoscopy and tube salvage
    • Salpingostomy (leave tube open) or Salpingotomy (close it)
  • Laparoscopy and salpingectomy
    • For recurrent ectopic on same side, rupture or abn tube
  • Laparotomy
    • Unstable and adhesions

Prognosis

• 90% of pregnancy related deaths
• Complications
  • Infertility
  • Risk of future ectopids
  • Shock