Antepartum Hemorrhage

Overview

• Definition: Antepartum hemorrhage (APH) is defined as bleeding from the genital tract occurring from 20 weeks 0 days of gestation until the onset of labor. It complicates approximately 3-5% of pregnancies and is a leading cause of maternal and perinatal morbidity and mortality worldwide.
• Epidemiology: APH is a significant obstetric emergency. Globally, it contributes substantially to maternal deaths. In developed countries, the incidence of severe APH (requiring transfusion or leading to adverse outcomes) is around 0.5-1%. It accounts for 20-25% of maternal deaths in some regions (e.g., Africa, Asia).
• Classification: APH is broadly classified by its source:
  • Placental Causes:
    • Placenta Previa: Implantation of the placenta over or near the cervical os.
    • Placental Abruption (Abruptio Placentae): Premature separation of a normally implanted placenta from the uterine wall.
    • Vasa Previa: Fetal blood vessels traversing the fetal membranes over the internal cervical os, unprotected by placental tissue or umbilical cord.
  • Non-Placental Causes:
    • Cervical Causes: Cervicitis, cervical polyps, cervical ectropion, cervical carcinoma.
    • Vaginal Causes: Vaginal lacerations, vaginitis, varices, trauma.
    • Uterine Causes: Uterine rupture (rare before labor, but possible with previous uterine surgery or trauma), marginal sinus rupture.
    • Unexplained Bleeding: In a significant proportion of cases, a cause is not identified (idiopathic).

Pathophysiology

• Mechanism:
  • Placenta Previa: As the lower uterine segment thins and dilates in the third trimester, the placenta overlying the cervix can shear, leading to bleeding from maternal decidual vessels. The bleeding is typically painless and bright red.
  • Placental Abruption: This involves hemorrhage into the decidua basalis, leading to separation of the placenta. The mechanism often involves a pathological uterine spiral artery, leading to decidual hemorrhage, hematoma formation, and subsequent placental detachment. Associated with vasoconstriction and ischemia.
  • Vasa Previa: Rupture of the unprotected fetal vessels traversing the membranes, particularly during membrane rupture (spontaneous or artificial), leads to fetal exsanguination.
  • Cervical/Vaginal Causes: Local inflammation, trauma, or structural abnormalities cause minor vessel rupture.
  • Uterine Rupture: Full-thickness disruption of the uterine wall, leading to significant hemorrhage, often from uterine vessels, and fetal extrusion into the peritoneal cavity.
• Risk Factors:
  • Placenta Previa: Previous C-section (dose-dependent, 1 prior C-section confers 2x risk, 3 prior 10x risk), multiparity, advanced maternal age (>35 years), multifetal gestation, prior placenta previa, smoking, cocaine use, endometritis, uterine curettage.
  • Placental Abruption: Hypertension (chronic or gestational), preeclampsia, prior abruption (recurrence risk 10-25%), trauma (e.g., motor vehicle accident, domestic violence), cocaine use, smoking, preterm premature rupture of membranes (PPROM), polyhydramnios (rapid decompression), short umbilical cord, uterine fibroids.
  • Vasa Previa: Low-lying placenta/placenta previa (especially if placenta migrates), bilobed or succenturiate-lobed placenta, in vitro fertilization (IVF), multifetal gestation.
  • Uterine Rupture: Previous uterine surgery (especially C-section with classical or T-incision, myomectomy), hyperstimulation with oxytocin or prostaglandins, grand multiparity, multiple gestation, trauma.
• Protective Factors: Generally, a healthy pregnancy with good antenatal care, avoidance of illicit drug use, and management of pre-existing hypertension are key. Planned C-sections for specific indications (e.g., placenta previa) can reduce severe hemorrhage risk.

Clinical Presentation

Signs and Symptoms

• Cardinal Features:
  • Vaginal Bleeding: The primary symptom. Character, amount, and associated pain are crucial discriminators.
  • Placenta Previa: Typically painless, bright red bleeding, often unprovoked. May be intermittent.
  • Placental Abruption: Painful vaginal bleeding (dark red), uterine tenderness, board-like abdomen, hypertonic contractions, non-reassuring fetal heart rate (FHR) patterns. Pain may precede bleeding.
  • Vasa Previa: Bleeding occurs with rupture of membranes (ROM), typically initially painless. Fetal distress is very rapid and severe.
  • Uterine Rupture: Sudden, sharp abdominal pain (often described as "tearing"), cessation of contractions (if in labor), FHR decelerations (often bradycardia), loss of fetal station, maternal hypovolemic shock.
• Early Signs:
  • Spotting or light bleeding without pain (can be physiologic or initial sign of previa).
  • Mild abdominal discomfort with dark red discharge (early abruption).
  • Decreased fetal movement.
• Advanced Signs:
  • Profuse, uncontrolled bleeding with signs of hypovolemic shock (tachycardia, hypotension, pallor, altered mental status).
  • Fetal distress (persistent bradycardia, late decelerations, decreased variability).
  • Severe, board-like uterine tenderness.
• Atypical Presentations:
  • Concealed Abruption: Hemorrhage is contained within the uterus, with minimal or no overt vaginal bleeding, leading to disproportionate maternal shock relative to visible blood loss.
  • Amniotic Fluid Embolism: Can mimic severe abruption or uterine rupture, often with similar hemorrhagic and shock features.

Physical Examination

• Inspection:
  • Assess general appearance: Pallor, diaphoresis, signs of shock.
  • Quantify visible blood loss: Estimate amount, note color (bright red vs. dark clots).
  • Abdominal contour: Uterine size, tenderness, guarding, rigidity (board-like abdomen in severe abruption).
  • Fetal position and presentation (Leopold maneuvers).
• Palpation:
  • Uterine palpation: Tenderness, tone (soft vs. hypertonic), contractions frequency, duration, intensity.
  • Fetal parts: Assess engagement, presentation.
• Special Tests:
  • NO DIGITAL VAGINAL EXAMINATION until placenta previa is definitively excluded by ultrasound.
  • Speculum Examination: To visualize the cervix and rule out local causes (cervicitis, polyps, lacerations, ectropion). Sample for cultures if infection suspected. Note origin of bleeding (cervical, vaginal, or fundal).
  • Fetal Cardiotocography (CTG): Continuous FHR monitoring to assess fetal well-being and identify distress.
  • Uterine activity monitoring: Assess contractions.

Diagnostic Approach

History Taking

• Key Questions:
  • Onset, duration, amount, color of bleeding: When did it start? How much? What color was the blood? Is it continuous or intermittent?
  • Associated symptoms: Any pain? Where? What kind of pain (sharp, cramping, dull)? Any uterine tenderness? Contractions?
  • Fetal activity: Has fetal movement changed?
  • Gestational age: Precise dating is crucial.
  • Risk factors: Prior C-sections, abruption, previa, history of hypertension, smoking, drug use, trauma, multiple gestation, IVF.
  • Previous pregnancies: Outcomes, complications.
  • Recent intercourse or trauma: May precipitate bleeding from local causes.
• Red Flags:
  • Significant bleeding (pad soaked in <1 hour).
  • Abdominal pain or uterine tenderness.
  • Signs of maternal hypovolemic shock.
  • Non-reassuring FHR.
  • History of placenta previa or C-section.

Laboratory Tests

• First-Line:
  • Complete Blood Count (CBC): Hemoglobin, hematocrit to assess anemia and blood loss, platelet count for coagulopathy.
  • Type and Screen/Crossmatch: Essential for potential blood transfusion.
  • Coagulation Profile (PT, aPTT, Fibrinogen): To assess for coagulopathy (especially in abruption). Fibrinogen <200 mg/dL is highly suggestive of severe abruption and impending coagulopathy.
  • Kleihauer-Betke Test (or flow cytometry for D antigen): To quantify amount of fetomaternal hemorrhage if Rh-negative mother, to determine appropriate dose of Rh immune globulin.
  • Urinalysis/Urine culture: Rule out urinary tract infection if indicated.
• Confirmatory:
  • No single lab test confirms specific causes of APH, rather, they support the clinical diagnosis and guide management. Imaging is key for placental causes.
• Monitoring:
  • Repeat CBC and coagulation profile as clinically indicated, especially with ongoing bleeding or transfusion.

Imaging

• Recommended:
  • Transabdominal Ultrasound with Transvaginal Ultrasound (TVUS): The gold standard for diagnosing placenta previa and evaluating placental position. TVUS is safe and more accurate than transabdominal ultrasound for placenta localization. Rule out placental anomalies (succenturiate lobe, bilobed placenta) that can be associated with vasa previa.
  • Ultrasound for Abruption: Findings include retroplacental hematoma, placental enlargement, or abnormal placental texture, but ultrasound has low sensitivity for abruption (only 2-25% detect a retroplacental hematoma), and a normal ultrasound does not rule it out. Diagnosis is primarily clinical.
  • Ultrasound for Vasa Previa: Can be diagnosed antenatally by color Doppler TVUS showing fetal vessels crossing the internal os, inserting into the membranes rather than the main placental mass.
• Advanced:
  • Magnetic Resonance Imaging (MRI): Occasionally used for complex posterior placenta previa, placenta accreta spectrum disorders, or when ultrasound is inconclusive, but usually not required for emergent APH diagnosis.

Management

Acute Management

The immediate focus is on maternal stabilization, assessment of fetal well-being, and identification of the cause. - Immediate (First-hour interventions): 1. Call for Help: Activate obstetric emergency team. 2. Maternal Stabilization: - Airway, Breathing, Circulation (ABC): Ensure patent airway, adequate oxygenation (administer O2 via non-rebreather mask at 10-12 L/min). - Intravenous Access: Establish two large-bore IV lines (16-gauge or larger). - Fluid Resuscitation: Infuse crystalloids (e.g., normal saline or lactated Ringer's) rapidly (e.g., 500-1000 mL bolus over 10-20 min), titrated to vital signs and urine output. - Blood Products: Send blood for Type & Screen/Crossmatch immediately. If severe hemorrhage, initiate uncrossmatched O-negative blood while waiting for crossmatched blood. Activate massive transfusion protocol if indicated. - Vital Signs: Closely monitor maternal heart rate, blood pressure, respiratory rate, oxygen saturation. Monitor urine output via Foley catheter. 3. Fetal Assessment: - Continuous Fetal Heart Rate (FHR) Monitoring: Apply continuous cardiotocography to assess fetal status. - Ultrasound: Confirm fetal viability, estimate gestational age, assess presentation, and quantify amniotic fluid. - Stabilization (Early management priorities): - Identify source of bleeding: Use speculum exam once placenta previa ruled out by ultrasound. - Determine etiology: Ultrasound for placental location. Clinical assessment for abruption. - Consult with multidisciplinary team: Obstetrics, anesthesiology, neonatology, blood bank. - Administer Rh immune globulin (RhoGAM): If mother is Rh-negative, administer RhIg (e.g., 300 mcg IM for 30 mL fetal blood), especially after a significant bleed. - Corticosteroids: If gestation is <34 weeks and delivery is anticipated, administer antenatal corticosteroids (e.g., betamethasone 12 mg IM every 24 hours for two doses) to promote fetal lung maturity. - Emergency (Crisis management): - Decision for Delivery: The primary management of severe APH (especially abruption or previa with significant unstable bleeding) is delivery. - Placenta Previa: Usually C-section. - Placental Abruption: Vaginal delivery often preferred if maternal-fetal status allows, especially if fetal demise or imminent vaginal delivery. C-section for non-reassuring FHR and live fetus. - Vasa Previa: Immediate C-section upon diagnosis/membrane rupture. - Uterine Rupture: Immediate C-section. - Resuscitative Hysterectomy: May be necessary if uterine atony or extensive lacerations are refractory to other hemostatic measures (e.g., in cases of placenta accreta spectrum or uterine rupture).

Chronic Management

• Pharmacological:
  • Tocolytics: Generally contraindicated in significant APH as they can delay delivery, increase blood loss, and mask signs of worsening abruption (e.g., magnesium sulfate might be considered for neuroprotection in preterm birth but not for uterine relaxation in active bleeding).
  • Iron supplementation: For chronic iron deficiency anemia post-hemorrhage.
• Non-pharmacological:
  • Expectant Management: For stable placenta previa without active bleeding and preterm gestation, expectant management in a hospital setting (or highly compliant outpatient) involves close monitoring, bed rest, and avoiding coitus.
  • Monitoring: Close antenatal surveillance for recurrent bleeding episodes, fetal growth restriction, and worsening anemia.

Treatment Algorithms

• First-Line:
  1. Assess ABCs, establish IV access, initiate fluid resuscitation.
  2. Monitor maternal vital signs and FHR continuously.
  3. Perform immediate ultrasound to determine placental location.
  4. If placenta previa confirmed: Avoid vaginal exam.
     • Stable mother/fetus, preterm: Expectant management (hospitalization, corticosteroids if <34 weeks, serial US).
     • Unstable mother/fetus, significant bleeding, term/near-term: Prepare for C-section.
  5. If placenta previa excluded, perform speculum exam to rule out vaginal/cervical causes.
  6. If abruption suspected (pain, tenderness, non-reassuring FHR):
     • Unstable mother/fetus: Immediate delivery (C-section if live fetus, vaginal if fetal demise or imminent).
     • Stable mother/fetus with mild abruption, preterm: Close observation, corticosteroids if <34 weeks.
  7. If vasa previa suspected/diagnosed antenatally: Elective C-section typically between 34-36 weeks after corticosteroids. If bleeding with ROM, immediate C-section.
  8. If uterine rupture suspected: Immediate C-section.
• Second-Line:
  • Blood product transfusion: Packed Red Blood Cells (PRBCs) for significant blood loss/anemia, Fresh Frozen Plasma (FFP) for coagulopathy, Platelets for thrombocytopenia, Cryoprecipitate for low fibrinogen.
  • Intensive Care Unit (ICU) admission: For severe shock, multiorgan dysfunction.
• Refractory Cases:
  • Damage control surgery: For ongoing hemorrhage not controlled by uterine repair or pharmacological agents (e.g., Bakri balloon, B-Lynch suture).
  • Hysterectomy: As a last resort for life-threatening hemorrhage (e.g., intractable uterine atony, placenta accreta spectrum, severe uterine rupture not amenable to repair).

Complications

• Common:
  • Maternal Anemia: From blood loss.
  • Premature Labor/Delivery: Hemorrhage is a common trigger for preterm birth.
  • Fetal Growth Restriction: Chronic abruption or placenta previa can be associated with impaired placental function.
• Serious:
  • Maternal Hemorrhagic Shock: Severe hypovolemia leading to organ dysfunction.
  • Disseminated Intravascular Coagulation (DIC): Most common with severe abruption, due to release of thromboplastin from the placental site.
  • Maternal Death: Directly from hemorrhage or its complications.
  • Fetal Hypoxia/Asphyxia leading to Fetal Demise: Due to uteroplacental insufficiency or acute blood loss.
  • Perinatal Mortality/Morbidity: Due to prematurity, hypoxia, or severe fetal anemia.
  • Postpartum Hemorrhage (PPH): Risk increased due to uterine atony (from prolonged labor, rapid delivery, or placental abnormalities), retained placental tissue, or coagulopathy.
  • Need for Hysterectomy: For uncontrollable bleeding.
• Long-term:
  • Recurrence of APH: Increased risk in subsequent pregnancies.
  • Psychological impact: PTSD, anxiety, depression for parents.
  • Chronic maternal health issues: Anemia, renal impairment (rare), pituitary necrosis (Sheehan's syndrome - rare).
  • Long-term child developmental issues: Related to prematurity, hypoxia.

Prognosis

• Factors:
  • Etiology of APH: Vasa previa with undiagnosed rupture has very poor fetal prognosis. Severe abruption has higher maternal and fetal morbidity/mortality.
  • Amount and rate of blood loss: More severe hemorrhage dictates worse prognosis.
  • Gestational age at onset: Preterm APH carries higher risks due to prematurity.
  • Timeliness of diagnosis and intervention: Rapid, appropriate management improves outcomes.
  • Access to resources: Blood products, critical care, experienced obstetric staff.
• Survival:
  • Maternal Mortality: Variable globally, significantly reduced in developed countries but still a leading cause.
  • Perinatal Mortality: Remains high with severe abruption (up to 20-30%) and vasa previa (up to 50-90% if not diagnosed antenatally and emergency C-section not performed). Improved significantly for previa with modern management.
• Quality of Life: Can be impacted by complications such as chronic anemia, PTSD, and the long-term sequelae of prematurity for the infant.

Prevention

• Primary: Preventing initial occurrence.
  • Smoking Cessation/Avoidance of Illicit Drugs (especially cocaine): Reduces risk of abruption.
  • Control of Chronic Hypertension: Before and during pregnancy.
  • Avoidance of unnecessary C-sections: To reduce risk of placenta previa in subsequent pregnancies.
  • Adequate prenatal nutrition: Folate supplementation may influence placental development, though direct link to APH prevention is less clear.
• Secondary: Early detection and intervention.
  • Routine Antenatal Ultrasound (20-week anatomy scan): To screen for placenta previa. If low-lying placenta is identified, a repeat ultrasound later in pregnancy (e.g., 32-34 weeks) is recommended to assess for "migration" and final position.
  • Screening for Vasa Previa: Considered in high-risk pregnancies (IVF, placenta previa, bilobed/succenturiate placenta) using color Doppler TVUS at 20 weeks.
  • Close monitoring of high-risk pregnancies: For conditions like preeclampsia, multiple gestation.
• Tertiary: Preventing complications.
  • Prompt evaluation and management of any vaginal bleeding in pregnancy.
  • Administering Rh immune globulin for Rh-negative mothers.
  • Administering antenatal corticosteroids for anticipated preterm birth.

Special Populations

• Pediatric: Not applicable (this is an antepartum condition).
• Geriatric: Advanced maternal age (>35 years) is a risk factor for placenta previa and other placental abnormalities, leading to increased risk of APH. Management principles remain the same but with heightened awareness of potential comorbidities and reduced physiological reserve.
• Pregnancy: This entire topic is pregnancy-specific. Key modifications include:
  • Fetal considerations: Impact on fetal well-being dictates urgency of intervention.
  • Unique anatomy/physiology: Uterine vessels, placental circulation, maternal adaptations to pregnancy.
  • Fetal lung maturity: Corticosteroids for preterm delivery.
  • Rh status: Rh immune globulin administration.
• Comorbidities:
  • Hypertension/Preeclampsia: Directly increases risk for abruption. Management involves controlling blood pressure while managing bleeding crisis.
  • Diabetes: Can increase risk of preeclampsia and vascular issues.
  • Coagulopathies: Pre-existing or acquired coagulopathies require careful assessment and management of bleeding.
  • Cardiac disease: Maternal cardiac disease complicates management of hypovolemic shock, requiring careful fluid resuscitation to avoid overload.

Clinical Pearls

• Diagnostic:
  • "Painless, bright red bleeding, often unprovoked" = Previa until proven otherwise.
  • "Painful, dark red bleeding, tender rigid uterus, FHR changes" = Abruption until proven otherwise.
  • Never perform a digital vaginal examination for APH until placenta previa has been excluded by ultrasound!
  • A normal ultrasound does not rule out placental abruption; clinical presentation is paramount.
  • Rapid fetal distress (sudden bradycardia, sinusoidal pattern) with rupture of membranes and slight bleeding strongly suggests vasa previa.
• Treatment:
  • ABC management is paramount. Always prioritize maternal stabilization.
  • Two large-bore IVs immediately.
  • Get blood ready immediately: Type & Screen/Crossmatch; consider uncrossmatched O-negative if severe.
  • Anticipate postpartum hemorrhage. Patients with APH are at high risk.
  • Be prepared for massive transfusion protocol in severe cases.
  • In uterine rupture, quick decision-making and immediate C-section are critical for fetal survival.
• Pitfalls:
  • Delaying definitive action: Hesitation in transfer, C-section decision, or blood transfusion.
  • Underestimating blood loss: Visual estimation is often inaccurate; look for changes in vital signs, urine output, and laboratory trends.
  • Ignoring subtle signs of shock: Tachycardia is often the first sign in pregnant women due to increased blood volume.
  • Performing digital vaginal exam prematurely: Can worsen bleeding in placenta previa.
  • Solely relying on ultrasound for abruption diagnosis: Clinical picture is more reliable.

Recent Updates

• Guidelines:
  • ACOG Practice Bulletin No. 172: Placenta Accreta Spectrum (2018; re-affirmed 2021) - Emphasizes early diagnosis and planned multidisciplinary delivery.
  • ACOG Practice Bulletin No. 204: Vaginal Birth After Cesarean (VBAC) (2019) - Reiterates the risks of uterine rupture with TOLAC.
  • RCOG Green-top Guideline No. 64: Placenta Praevia and Placenta Accreta: Diagnosis and Management (2018) - Recommends TVUS for definitive diagnosis of placenta previa and early MRI for suspected accreta.
• Evidence:
  • Increased recognition of placenta accreta spectrum disorders as a major contributor to severe APH and maternal morbidity, particularly in the context of prior C-sections.
  • Renewed emphasis on multidisciplinary team approach for severe APH management, including obstetricians, anesthesiologists, neonatologists, interventional radiologists, and blood bank personnel.
  • Importance of patient blood management strategies to optimize hemoglobin levels and minimize allogeneic blood transfusions, where possible.
• Controversies:
  • The optimal gestational age for planned delivery in stable placenta previa and vasa previa balancing prematurity risks vs. hemorrhage risk.
  • The role of prophylactic interventions (e.g., cerclage, prophylactic uterine embolization) in specific high-risk scenarios for APH.
  • Management of very early, minimal abruption (expectant vs. delivery).

Key References

• Guidelines:
  • American College of Obstetricians and Gynecologists (ACOG) Practice Bulletins on Placenta Previa, Placental Abruption, and VBAC.
  • Royal College of Obstetricians and Gynaecologists (RCOG) Green-top Guidelines on Placenta Praevia and Placenta Accreta.
  • World Health Organization (WHO) Guidelines for the management of postpartum hemorrhage and retain placenta (relevant for overall obstetric hemorrhage management).
• Studies:
  • Silver, R. M. (2015). Abnormal placentation: placenta previa, vasa previa, and accreta. Obstetrics & Gynecology, 126(3), 654-681. (Comprehensive review on abnormal placentation).
  • Tikkanen, M. (2011). Placental abruption: epidemiology, risk factors, and consequences. Acta Obstetricia et Gynecologica Scandinavica, 90(2), 140-149. (Epidemiological study on abruption).
• Reviews:
  • UpToDate: "Clinical manifestations and diagnosis of placenta previa," "Placental abruption: Management," "Vasa previa: Management."
  • Creasy and Resnik's Maternal-Fetal Medicine (8th ed.). Chapters on Obstetrical Hemorrhage and Abnormal Placentation.

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Disclaimer: This information is intended for educational purposes only and should not be considered medical advice. Clinical decisions must always be made by a qualified healthcare professional, taking into account individual patient circumstances and the latest available evidence. Rapidly evolving medical knowledge necessitates continuous professional development. Always consult primary sources for dosages, criteria, and guidelines.