Vaginal Bleeding in Late Pregnancy

1. Vaginal Bleeding in Late Pregnancy

2. Objectives • Identify major causes of vaginal bleeding in the second half of pregnancy • Describe a systematic approach to identifying the cause of bleeding • Describe specific treatment options based on diagnosis

3. Causes of Late Pregnancy Bleeding • Placenta Previa • Abruption • Ruptured vasa previa • Uterine scar disruption • Cervical polyp • Bloody show • Cervicitis or cervical ectropion • Vaginal trauma • Cervical cancer Life-Threatening

4. Prevalence of Placenta Previa • Occurs in 1/200 pregnancies that reach 3rd trimester • Low-lying placenta seen in 50% of ultrasound scans at 16-20 weeks • 90% will have normal implantation when scan repeated at >30 weeks • No proven benefit to routine screening ultrasound for this diagnosis

5. Risk Factors for Placenta Previa • Previous cesarean delivery • Previous uterine instrumentation • High parity • Advanced maternal age • Smoking • Multiple gestation

6. Morbidity with Placenta Previa • Maternal hemorrhage • Operative delivery complications • Transfusion • Placenta accreta, increta, or percreta • Prematurity

7. Patient History – Placenta Previa • Painless bleeding • 2nd or 3rd trimester, or at term • Often following intercourse • May have preterm contractions • “Sentinel bleed”

8. Physical Exam – Placenta Previa • Vital signs • Assess fundal height • Fetal lie • Estimated fetal weight (Leopold) • Presence of fetal heart tones • Gentle speculum exam • NO digital vaginal exam unless placental location known

9. Laboratory – Placenta Previa • Hematocrit or complete blood count • Blood type and Rh • Coagulation tests • While waiting – serum clot tube taped to wall

10. Ultrasound – Placenta Previa • Can confirm diagnosis • Full bladder can create false appearance of anterior previa • Presenting part may overshadow posterior previa • Transvaginal scan can locate placental edge and internal os

11. Treatment – Placenta Previa • With no active bleeding • Expectant management • No intercourse, digital exams • With late pregnancy bleeding • Assess overall status, circulatory stability • Full dose Rhogam if Rh- • Consider maternal transfer if premature • May need corticosteroids, tocolysis, amniocentesis

12. Double Set-Up Exam • Appropriate only in marginal previa with vertex presentation • Palpation of placental edge and fetal head with set up for immediate surgery • Cesarean delivery under regional anesthesia if: • Complete previa • Fetal head not engaged • Non-reassuring tracing • Brisk or persistent bleeding • Mature fetus

13. Placental Abruption • Premature separation of placenta from uterine wall • Partial or complete • “Marginal sinus separation” or “marginal sinus rupture” • Bleeding, but abnormal implantation or abruption never established

14. Epidemiology of Abruption • Occurs in 1-2% of pregnancies • Risk factors • Hypertensive diseases of pregnancy • Smoking or substance abuse (e.g. cocaine) • Trauma • Overdistention of the uterus • History of previous abruption • Unexplained elevation of MSAFP • Placental insufficiency • Maternal thrombophilia/metabolic abnormalities

15. Abruption and Trauma • Can occur with blunt abdominal trauma and rapid deceleration without direct trauma • Complications include prematurity, growth restriction, stillbirth • Fetal evaluation after trauma • Increased use of FHR monitoring may decrease mortality

16. Bleeding from Abruption • Externalized hemorrhage • Bloody amniotic fluid • Retroplacental clot • 20% occult • “uteroplacental apoplexy” or “Couvelaire” uterus • Look for consumptive coagulopathy

17. Patient History - Abruption • Pain = hallmark symptom • Varies from mild cramping to severe pain • Back pain – think posterior abruption • Bleeding • May not reflect amount of blood loss • Differentiate from exuberant bloody show • Trauma • Other risk factors (e.g. hypertension) • Membrane rupture

18. Physical Exam - Abruption • Signs of circulatory instability • Mild tachycardia normal • Signs and symptoms of shock represent >30% blood loss • Maternal abdomen • Fundal height • Leopold’s: estimated fetal weight, fetal lie • Location of tenderness • Tetanic contractions

19. Ultrasound - Abruption • Abruption is a clinical diagnosis! • Placental location and appearance • Retroplacental echolucency • Abnormal thickening of placenta • “Torn” edge of placenta • Fetal lie • Estimated fetal weight

20. Laboratory - Abruption • Complete blood count • Type and Rh • Coagulation tests + “Clot test” • Kleihauer-Betke not diagnostic, but useful to determine Rhogam dose • Preeclampsia labs, if indicated • Consider urine drug screen

21. Sher’s Classification - Abruption mild, often retroplacental clot identified at delivery • Grade I • Grade II • Grade III with fetal demise • III A - without coagulopathy (2/3) • III B - with coagulopathy (1/3) tense, tender abdomen and live fetus

22. Treatment – Grade II Abruption • Assess fetal and maternal stability • Amniotomy • IUPC to detect elevated uterine tone • Expeditious operative or vaginal delivery • Maintain urine output > 30 cc/hr and hematocrit > 30% • Prepare for neonatal resuscitation

23. Treatment – Grade III Abruption • Assess mother for hemodynamic and coagulation status • Vigorous replacement of fluid and blood products • Vaginal delivery preferred, unless severe hemorrhage

24. Coagulopathy with Abruption • Occurs in 1/3 of Grade III abruption • Usually not seen if live fetus • Etiologies: consumption, DIC • Administer platelets, FFP • Give Factor VIII if severe

25. Epidemiology of Uterine Rupture • Occult dehiscence vs. symptomatic rupture • 0.03 – 0.08% of all women • 0.3 – 1.7% of women with uterine scar • Previous cesarean incision most common reason for scar disruption • Other causes: previous uterine curettage or perforation, inappropriate oxytocin usage, trauma

26. Risk Factors – Uterine Rupture

27. Morbidity with Uterine Rupture • Maternal • Hemorrhage with anemia • Bladder rupture • Hysterectomy • Maternal death • Fetal • Respiratory distress • Hypoxia • Acidemia • Neonatal death

28. Patient History – Uterine Rupture • Vaginal bleeding • Pain • Cessation of contractions • Absence of FHR • Loss of station • Palpable fetal parts through maternal abdomen • Profound maternal tachycardia and hypotension

29. Uterine Rupture • Sudden deterioration of FHR pattern is most frequent finding • Placenta may play a role in uterine rupture • Transvaginal ultrasound to evaluate uterine wall • MRI to confirm possible placenta accreta • Treatment • Asymptomatic scar disruption – expectant management • Symptomatic rupture – emergent cesarean delivery

30. Vasa Previa • Rarest cause of hemorrhage • Onset with membrane rupture • Blood loss is fetal, with 50% mortality • Seen with low-lying placenta, velamentous insertion of the cord or succenturiate lobe • Antepartum diagnosis • Amnioscopy • Color doppler ultrasound • Palpate vessels during vaginal examination

31. Diagnostic Tests – Vasa Previa • Apt test – based on colorimetric response of fetal hemoglobin • Wright stain of vaginal blood – for nucleated RBCs • Kleihauer-Betke test – 2 hours delay prohibits its use

32. Management – Vasa Previa • Immediate cesarean delivery if fetal heart rate is non-reassuring • Administer normal saline 10 – 20 cc/kg bolus to newborn, if found to be in shock after delivery

33. Summary • Late pregnancy bleeding may herald diagnoses with significant morbidity/mortality • Determining diagnosis important, as treatment dependent on cause • Avoid vaginal exam when placental location not known