Bleeding in early pregnancy
Obstetrics
Emergency department or early pregnancy unit, under 20 weeks
The first question
Is she stable, and where is the pregnancy?
Two patients: the gestational age and the maternal stability first, then the fetal status.
- 01
Stability
Pulse, blood pressure, pallor, the amount of bleeding. Shock in early pregnancy is a ruptured ectopic until proven otherwise.
- 02
Confirm pregnancy and date it
Urine or serum hCG; last menstrual period; any prior scan showing an intrauterine pregnancy changes everything.
- 03
Locate it
Transvaginal ultrasound: intrauterine (viable, uncertain viability, or loss), ectopic, or pregnancy of unknown location.
- 04
Decide
Threatened miscarriage: reassure and safety-net. Loss: three options. Ectopic: expectant, methotrexate or surgery. Unknown location: serial hCG with return advice.
- 05
Rh status
Anti-D where indicated.
Where it is
Each opens the structure on the 3D pelvis.
History that discriminates
- Amount and character of bleeding, clots or tissue
- Pain: site, side, shoulder tip
- Syncope or presyncope
- Last menstrual period and its certainty
- Prior ectopic, tubal surgery, IUD, assisted reproduction
- Prior scans this pregnancy
Examination that discriminates
- Vital signs including postural change
- Abdominal tenderness and peritonism
- Speculum: source and amount of bleeding, cervical os open or closed, tissue at the os
- Bimanual: adnexal tenderness or mass, cervical motion tenderness; gently, and not if a praevia is possible (not relevant before 20 weeks)
Investigations
- Serum hCG (and repeat at 48 hours if location unknown)
- CBC, blood group and antibody screen
- Transvaginal ultrasound
- Bedside FAST if unstable
What the image changes
The differential
| Diagnosis | Favours | Against | Urgency |
|---|---|---|---|
| Threatened miscarriage | Closed os, live intrauterine pregnancy on scan | Open os, tissue passed | routine |
| Early pregnancy loss (inevitable, incomplete, missed) | Open os, tissue, scan criteria met | Live pregnancy on scan | urgent |
| Ectopic pregnancy | Unilateral pain, empty uterus, adnexal mass, free fluid, plateauing hCG, risk factors | Intrauterine pregnancy confirmed (heterotopic is rare outside IVF) | emergent |
| Molar pregnancy | Hyperemesis, uterus large for dates, very high hCG, snowstorm on scan | Normal hCG for dates, normal scan | urgent |
| Cervical or vaginal cause | Postcoital bleeding, a visible ectropion, polyp or lesion; normal pregnancy on scan | Bleeding from the os | routine |
| Implantation bleeding | Light spotting around the missed period, live pregnancy, no pain | Any of the above | routine |
Pitfalls this pathway refuses
- Reassuring a patient with a positive test and an empty uterus without a plan for the hCG
- Calling a 3 mm embryo without a heartbeat a loss
- Diagnosing miscarriage on a history of tissue passed without a scan: the ectopic bleeds too
- Forgetting anti-D