Vaginal bleeding – early pregnancy

Vaginal bleeding in early pregnancy is a common problem affecting approximately 25 % of all clinically diagnosed pregnancies. Of these about 50 % will be due to a failed pregnancy.

Introduction

Bleeding in early pregnancy affects ~25% of clinically diagnosed pregnancies, with ~50% due to failed pregnancy. It is commonly defined as vaginal bleeding during the first trimester (up to 12 weeks), though some definitions extend to 20 weeks.

Ectopic pregnancy must always be excluded first.

Modern evaluation of stable patients relies on ultrasound and quantitative beta-HCG, as clinical examination alone is unreliable. Speculum examination is required in patients with heavy bleeding or shock.

Miscarriage is defined as pregnancy loss before 20 completed weeks gestation or fetal weight <400 g if gestation is unknown.

Related documents:

  • Threatened Miscarriage
  • Ectopic Pregnancy
  • Anti-D Administration

Pathophysiology

Causes of early pregnancy bleeding:

  1. Ectopic pregnancy
  2. Miscarriage:
    • Threatened
    • Failed pregnancy
    • Incomplete (or inevitable)
    • Complete
    • Septic
  3. Trophoblastic disease (molar pregnancy)
  4. Incidental causes (see Non-Pregnancy Related Vaginal Bleeding)

Clinical Features

Key history points:

  • Pain: More intense than in threatened miscarriage, especially if ectopic
  • Bleeding: Heavier than in threatened miscarriage
    • Presence of clots = heavier bleeding
    • Number of pads used can help quantify loss
  • POC passage: Unreliable marker of complete miscarriage

Key examination points:

  • Haemodynamic stability:
    • Hypotension + tachycardia = blood loss
    • Hypotension + bradycardia = cervical (vagal) shock
  • Abdominal tenderness: Suggests ectopic
  • PV examination:
    • Indicated for heavy or recurrent bleeding
    • May reveal POC, cervical motion tenderness, or bleeding source

Investigations

Bloods:

  • FBE
  • Quantitative Beta-HCG (if diagnosis uncertain)
  • Blood group (anti-D, crossmatch if needed)

If sepsis suspected:

  • CRP
  • Blood cultures
  • Vaginal swabs for M&C

Ultrasound:

  • Confirms failed pregnancy using:
    • CRL >6–10 mm with no cardiac activity
    • Gestational sac >20–25 mm with no fetal pole
  • Pregnancy of unknown location (elevated HCG, no visible IUP or ectopic)

Management

Haemodynamically unstable patients:

  1. ABCs, fluids, blood products
  2. Analgesia/sedation
  3. Os clearance (for cervical shock due to clots/POC)
  4. Ergometrine 250 mcg IM (if ongoing bleeding)
  5. Anti-D administration
  6. Antibiotics (only if septic abortion suspected)
  7. Surgical evacuation if bleeding persists

Haemodynamically stable patients:

  1. Anti-D administration
  2. Analgesia (oral)
  3. Management options:
    • Expectant (conservative): ~75% success, more prolonged bleeding/pain
    • Medical: Prostaglandin E1 (e.g., misoprostol)
    • Surgical: Elective cervical dilation + curettage

Patient preference plays a major role in choosing a management approach

Disposition

  • Close follow-up is essential
  • Advise return for ongoing bleeding, pain, fever, or discharge
  • Referral to psychological support services as needed

References

FOAMed

Publications

Fellowship Notes

Dr Jessica Hiller LITFL Author

Doctor at King Edward Memorial Hospital in Western Australia. Graduated from Curtin University in 2023 with a Bachelor of Medicine, Bachelor of Surgery. I am passionate about Obstetrics and Gynaecology, with a special interest in rural health care.

Dr James Hayes LITFL author

Educator, magister, munus exemplar, dicata in agro subitis medicina et discrimine cura | FFS |

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