🩸 Placenta Previa vs Abruption
Painless bright bleeding or a rigid painful uterus. The pair that appears on nearly every maternity exam, and the exam you must never perform.
⚖️ The comparison that answers the question
Two causes of third-trimester bleeding, and they are opposites in almost every respect.
Painless + bright red = previa. Painful + board-like uterus = abruption.
| PLACENTA PREVIA | ABRUPTIO PLACENTAE | |
|---|---|---|
| What it is | Placenta implanted over the cervix | Placenta separates early from the wall |
| Bleeding | Bright red, PAINLESS | Dark red, PAINFUL — may be concealed |
| Uterus | Soft, relaxed, non-tender | Rigid, board-like, very tender |
| Onset | Often sudden but painless | Sudden, with constant pain |
| Fetal heart | Usually reassuring at first | Distress early — late decelerations |
| Risk factors | Prior C-section, multiparity, prior previa, age >35 | Hypertension, trauma, cocaine, smoking, PROM |
| Vaginal exam | NEVER | Not typically |
| Delivery | C-section if complete | Usually emergency C-section |
Never perform a vaginal or digital cervical exam when placenta previa is suspected. The examining finger can tear the placenta and cause catastrophic hemorrhage.
Diagnosis is made by ultrasound — safe, and definitive.
👀 Recognizing each one
🩸 Previa
- Painless bright red bleeding, often first noticed on waking
- Uterus soft and non-tender
- Fetal position often abnormal — the placenta blocks engagement
- Bleeding may stop and recur
🚨 Abruption
- Sudden constant pain, often described as tearing
- Rigid, board-like uterus that does not relax
- Bleeding may be concealed behind the placenta — so the visible loss underestimates the real loss
- Signs of shock out of proportion to what you can see
⭐ The concealed bleed
In abruption, blood can be trapped behind the placenta. A rising fundal height, worsening pain and shock with little visible bleeding is a concealed abruption.
Trust the vital signs, not the pad count.
🩺 Nursing care for both
Immediate priorities
- Nothing by mouth — surgery may be imminent
- Weigh pads to quantify blood loss (1 g ≈ 1 mL)
- Strict input and output; indwelling catheter
- RhoGAM if the mother is Rh negative — any bleeding event can sensitize her
- Steroids to mature fetal lungs if preterm delivery is likely
🚨 The complication to watch for
DIC is a real risk in abruption — the damaged placenta releases thromboplastin, which consumes clotting factors.
Watch for bleeding from IV sites, gums and the nose, petechiae, and oozing that will not stop. Labs: low platelets, low fibrinogen, prolonged PT/aPTT, raised D-dimer.
🎯 NCLEX traps
- No vaginal exam with suspected previa — ultrasound only
- Painless bright = previa. Painful rigid = abruption.
- Concealed abruption: shock out of proportion to visible bleeding
- Hypertension and cocaine are the classic abruption risks
- Two large-bore IVs, left side, oxygen — for both