Vaginal bleeding – Miscarriage

Bleeding in early pregnancy is commonly defined as vaginal bleeding during the first trimester, however some definitions extend this to an arbitrary figure of 20 weeks.

Ectopic pregnancy must always be considered in the first instance.

Clinical examination alone is unreliable in the modern assessment of the stable patient with mild early pregnancy bleeding. It is best assessed by ultrasound and quantitative beta HCG levels. ¹

Patients with heavy bleeding, circulatory shock or vagal shock will need speculum examination as part of their resuscitative management. ¹

Definition

A miscarriage is defined as a pregnancy loss occurring before 20 completed weeks gestation or a foetus < 400 grams weight if the gestation is unknown.]

Complete miscarriage: all the tissue from the pregnancy has been passed, there are no products of conception seen on ultrasound

Incomplete miscarriage: a non-viable pregnancy on ultrasound where some of the products of conception have been passed, but some remain in the uterus

Missed miscarriage: non-viable pregnancy on ultrasound, cervix is closed, and no products of conception have been passed.

Pathophysiology

The causes of bleeding in early pregnancy include:

• Ectopic pregnancy.
• Abortion (miscarriage):
  • Threatened.
  • Failed pregnancy:
  • Incomplete (or inevitable).
  • Complete
  • Septic
• Trophoblastic disease (or “molar” pregnancy)
• Incidental:
  • This is due to non-pregnancy related pathology

Clinical Features

The clinical features of a miscarriage (or failed pregnancy) include:

Important points of History:

1. Pain:
   • Pain is usually more significant than in cases of threatened miscarriage, particularly in the case of ectopic pregnancy. 
2. Bleeding:
   • This is usually more severe than in the case of threatened abortion.
   • Estimating the amount of vaginal bleeding is somewhat subjective.
     More objective measures include:
     • The presence of clots, (suggests a relatively heavy bleed)
     • Number of pads used
     • Bleeding of a degree which is greater than a woman’s normal period carries a worse prognosis
3. POC:
   • A history of the passage of “POC” is unreliable in making a definitive statement about the viability of a pregnancy.
   • Blood clots or decidual cast may be misinterpreted as the POC.
   • Correct identification of the POC does not exclude the possibility of a live twin (or of the rare situation of a coexistent ectopic twin pregnancy).      

Important points of Examination:

1. Hemodynamic stability:
   • Hypotension and tachycardia suggest significant blood loss
   • Hypotension and relative bradycardia may indicate cervical shock
2. Abdomen:
   • Significant tenderness is suggestive of ectopic pregnancy.
3. PV examination:
   • When there is significant or recurring blood loss, or if there is significant pain, then PV examination is warranted
   • PV examination is both diagnostic and therapeutic.
   • POC may be identified

POC or clot present within the os can cause bleeding and/or cervical shock.

Investigations

Blood tests:

1. FBE
2. Beta HCG (if clinical uncertainty).
3. Blood group (for the determination of the need for the administration of anti-D) and cross match as clinically indicated.

If sepsis is suspected:

1. CRP (if sepsis suspected)
2. Blood cultures
3. Vaginal swabs for M&C

Ultrasound:

A failed pregnancy is now defined on ultrasound criteria.

Criteria includes:

• The finding of a crown – rump length (CRL) greater than 6-10 mm
  With
• No cardiac activity
  Or
• A gestational sac greater than 25 mm with no fetal pole (“blighted ovum”)

Pregnancy of unknown location:

When no pregnancy can be identified on ultrasound, yet the beta HCG is elevated, a pregnancy of unknown location is diagnosed ie. it could be intrauterine, but the pregnancy is too early to be seen on ultrasound, or it could be an ectopic pregnancy.

Management

Haemodynamically unstable patients:

1. Resuscitate the patient: give fluid or blood products as required
2. Analgesia/ sedation: give as clinically indicated
3. PV examination
   • Blood clot within the os can result in cervical shock, a vagally mediated reaction that results in bradycardia and hypotension.  Clearing the products of conception from the os resolves the shock.
4. Ergometrine:
   • If fluid and os clearance fails to correct ongoing bleeding, then ergometrine may be given if the diagnosis of miscarriage is clear
5. Anti-D:
   • Evaluate the need for anti-D with any bleeding that occurs during pregnancy
6. Antibiotics: if suspecting septic abortion.
7. Surgical: emergency surgical management may ultimately be required to control bleeding not controlled by other means.

Haemodynamically stable patients:

1. Check Rhesus D antigen and antibody status if a negative blood group
2. Analgesia as needed

There are three options available:

Expectant (or conservative):

• Success is variable, but some literature quotes a 75% success rate. ²
• It is usually associated with a slightly prolonged period of bleeding and pai
• Follow up required in 7-14 days to evaluate

Medical management:

• Misoprostol
  • Administer 800mcg vaginally or sublingually
  • Contraindications:
    • Severe asthma
    • Hypertension
    • Glaucoma
    • Mitral stenosis
    • Sickle cell anaemia
    • Allergy to misoprostol
  • Side effects:
    • Nausea, vomiting, diarrhoea
    • Fevers
• Follow up required at 7 days for need of further medical or surgical management

Surgical management:

• This is by cervical dilation and curettage.
• Indications:
  • Heavy bleeding or prolonged symptoms
  • Failed conservative or medical management
  • Choice of the patient

Disposition

• Ensure close follow-up
• Advise patients to return for review if there is ongoing bleeding (soaking pads every 1-2 hours), pain, or fever and discharge
• Referral for psychological support may be required

---

References

FOAMed

• Quo M. Abnormal vaginal bleeding. CCC
• Hiller J, Yarwood L. Vaginal bleeding – nonpregnant. FFS
• Yarwood L, Hiller J. Vaginal bleeding – early pregnancy. FFS
• Hiller J, Yarwood L. Vaginal bleeding – miscarriage. FFS
• Yarwood L, Hiller J. Septic abortion. FFS
• Rippey J. Ultrasound Case 075. LITFL
• Rippey J. Ultrasound Case 029. LITFL
• Mackenzie J, Beech A. Procedure: Speculum examination. LITFL

Publications

• Nanda K, Lopez LM, Grimes DA, Peloggia A, Nanda G. Expectant care versus surgical treatment for miscarriage. Cochrane Database of Systematic Reviews 2012, Issue 3.
• Nice guideline. Ectopic pregnancy and miscarriage: diagnosis and initial management. NICE guideline. 2019, April, updated 2023.