Bleeding in Pregnancy OSCE - Placenta Previa

Case Overview

• Age/Sex: 27-year-old female
• Occupation: Primary school teacher
• Setting: Tertiary hospital Emergency Department, obstetric triage
• Chief complaint: "I’m bleeding from my vagina during pregnancy"

Patient Script

Who I Am

I’m 27, I teach kids, and I’m about eight months pregnant.

What Brings Me In

I woke up this morning and found a lot of bright red blood in my underwear and I felt lightheaded, so I came to the hospital.

My Story

I’m 32 weeks pregnant. About 2 hours ago I noticed a sudden gush of bright red vaginal bleeding while I was walking to the bathroom. I had a heavier episode about 30 minutes before arriving and felt a bit dizzy and sweaty. I have had no strong belly pain—just a little pressure at times—but it hasn’t been crampy or painful like period pain. I haven’t broken my waters. Earlier in the pregnancy I had a couple of small twinges and a bit of spotting around 12 weeks that stopped by itself.

I had one previous pregnancy that ended with a caesarean section 3 years ago after my baby was stuck; I also had one first-trimester miscarriage two years ago that was managed without surgery. I smoke a few cigarettes sometimes when I’m stressed, and I had sex two days ago but it was gentle. I was fine until this morning when the bleeding started suddenly and a lot of it came out quickly.

My Medical Background

• Past medical history: previous caesarean section 3 years ago; one spontaneous miscarriage (first trimester)
• Medications: prenatal vitamins daily, no blood thinners
• Allergies: none known
• Social: occasional smoker (approx 5 cigarettes/week), lives with partner, works full time
• Obstetric: G3P1 at 32 weeks gestation
• Family history: mother with hypertension; no bleeding disorders

What I Think & Worry About

• I think something is wrong with the baby or the placenta.
• I’m really worried I might lose the baby or I could need an emergency operation.
• I want to know whether the baby is OK and whether I’ll need to have the baby delivered now.

If You Ask Me About Other Symptoms...

• Abdominal pain: "I don’t have any bad cramping or severe belly pain — it’s mainly the bleeding and feeling faint."
• Fetal movements: "I’ve noticed the baby moving less in the last 6–12 hours, not as much as usual." (reduced movements)
• Recent trauma: "No, I haven’t fallen or hit my tummy."
• Vaginal discharge or itching: "I sometimes have a bit of sticky white discharge, but no itch—nothing like that now, just blood." (red herring)
• Fever/illness: "No fever or chills, I don’t feel sick otherwise." (helps rule out infection)
• Medications/substances: "I don’t take anything except prenatal vitamins; I’ll admit I smoke a little sometimes." (risk factor)
• Prior procedures: "I had a C-section with my last baby." (important risk factor)

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Clinical Summary

Examination

• General: pale, diaphoretic, anxious woman
• Vital signs: BP 88/56 mmHg, HR 120 bpm (sinus on monitor), RR 22/min, Temp 36.5°C, SpO2 98% on room air
• Abdominal exam: fundal height ~32 cm; uterus soft and non-tender; no focal uterine tenderness or hypertonus
• External genitalia/speculum: active bright red bleeding pooling in posterior fornix; no obvious cervical polyp seen on speculum
• No loss of fetal station performed; digital vaginal examination avoided until placenta position clarified
• Fetal monitoring: continuous CTG showing baseline fetal heart rate ~110 bpm with reduced variability and intermittent late decelerations

Investigations

• Hb: 7.8 g/dL (marked anemia, likely acute blood loss)
• Hct: 24%
• Platelets: 185 x10^9/L (normal)
• Coagulation: PT 12s (normal), APTT 32s (normal), fibrinogen 2.1 g/L (lower end; monitor for consumption)
• Blood group & antibody screen: O negative (mother Rh negative) — urgent crossmatch required
• Kleihauer test: pending (to assess fetomaternal haemorrhage)
• Urinalysis: negative for infection (red herring ruling out UTI as cause of bleeding)
• High-resolution obstetric ultrasound (transabdominal then transvaginal when appropriate): placenta anterior and low-lying, covering the internal cervical os (major/complete placenta previa) — confirmed on transvaginal study
• Portable bedside pelvic ultrasound: large intravaginal/pooling blood noted

Diagnosis

Primary: Major placenta previa (complete placenta previa) at 32 weeks gestation causing acute, severe antepartum hemorrhage

• Evidence: sudden painless bright red bleeding in third trimester, history of prior C-section (risk factor), ultrasound showing placenta covering internal os, haemodynamic instability, low Hb and fetal distress on CTG.

Differential diagnoses (with reasoning):

• Placental abruption: usually painful with a tender, hypertonic uterus and often associated with concealed bleeding — less likely given absent uterine tenderness/rigidity and painless presentation.
• Vasa previa: would present with fetal bradycardia immediately after membranes rupture and fetal blood loss; there is no history of membrane rupture and the ultrasound localizes the placenta to the lower segment rather than velamentous cord over os.
• Cervical pathology (erosion, polyp, cervicitis): can cause bleeding but usually not massive hemorrhage leading to hemodynamic instability; speculum exam did not identify an obvious cervical lesion.

Management

• Immediate resuscitation: two large-bore IV cannulas, O-negative blood available and crossmatched; commence balanced crystalloid boluses while preparing for transfusion.
• Transfuse PRBCs urgently (initially 2 units, titrate to hemodynamics and Hb), send further crossmatch and request more units.
• Continuous maternal monitoring and continuous fetal cardiotocography.
• Obstetrics and anesthesia urgent review — prepare for possible emergency Caesarean section due to ongoing bleeding and non-reassuring fetal trace.
• Avoid further digital vaginal examinations until placenta location confirmed by ultrasound.
• Give corticosteroids for fetal lung maturation (e.g., betamethasone) if immediate delivery can be deferred and time permits; in this case give as soon as practical if delivery is not instantaneous.
• Give anti-D immunoglobulin to the Rh-negative mother as soon as practicable and perform Kleihauer to quantify fetomaternal haemorrhage.
• Consider giving broad-spectrum antibiotics at time of operative delivery per local guidelines.
• Continuous assessment of coagulation and replace blood products as needed (platelets, FFP, cryoprecipitate) if coagulopathy develops.
• Provide clear explanation, obtain informed consent for possible urgent Caesarean, and offer emotional support; arrange neonatal team at delivery.

Key Learning Points

• Placenta previa typically presents in the third trimester with sudden, painless, bright red vaginal bleeding; prior uterine surgery (e.g., C-section) increases risk.

• Avoid digital vaginal examinations until placenta previa is excluded by ultrasound; initial management is maternal resuscitation, fetal monitoring, urgent obstetric review, and preparation for Caesarean delivery if bleeding is severe or fetal distress is present.

• In any antepartum hemorrhage, secure IV access, crossmatch blood, give anti-D to Rh-negative mothers, and give corticosteroids if delivery before 34–37 weeks is anticipated.