bleeding late in pregnancy

Bleeding Late in Pregnancy

When the placenta misbehaves

Grace Cavallaro MD, FACOG

ObjectivesObjectives

• Identify major causes of vaginal bleeding second half of pregnancy

• Describe a systematic approach to identify the cause of bleeding

• Describe specific treatment options based on diagnosis

Causes of Late Pregnancy Bleeding

• Placenta Previa• Abruption• Ruptured Vasa Previa• Uterine Scar Disruption• Cervical Polyp• Bloody Show• Cervicitis• Vaginal Trauma• Cervical Cancer

LifeThreatening*

Placenta Previas

Placenta Previas

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 @ >30 weeks– No proven benefit to routine screening

ultrasound for this diagnosis.

Risk factors for previa

• Previous Cesarean Sections• Previous Uterine Instrumentation• High Parity• Advancing Maternal Age

– Women over 40 have a RR of 9.0

• Smoking• Multiple Gestation

Morbidity with Placenta Previa

• Maternal Hemorrhage

• Operative Delivery Complications

• Transfusion

• Placenta accreta, increta or percreta

• Prematurity

Placenta Migration

• Migration means the dynamic relationship between the placenta and the internal os

• Trophotropism vs elongating lower uterine segment!

Previous C-sections and Previas

Number of Previous C-sections

Relative Risk for a Previa

1 4.5

2 7.4

3 6.5

4 or more 44.9

Anath ObGyn 1996

Patient History - Placenta Previa

• Painless Bleeding*– 2nd or 3rd trimester, or at term– Often following intercourse– May have preterm contractions*

• Sentinel Bleed– From large central previa– @ 26-28 weeks gestation

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 exam unless placental location known

Speculum exam revealing an anterior placenta previa

Laboratory - Placenta Previa

• Hematocrit or complete blood count

• Blood Type and Rh

• Coagulation tests

• (While waiting - serum clot tube taped to the wall)

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

The Placenta’s Ultrasound Appearance

Echodense placental tissue

Echolucent myometrialArea rich in blood supply

Vagina and Cervix meet at 90 degrees

Careful insertion of the vaginal probe midway into the vagina will image the LUS and the cervical os

Complete Previa - Ultrasound

c

c

Posterior Previa

Transvaginal ScanPosterior PlacentaPrevia

False Previa

Lower placental border

c

Full bladderNo Previa

False Previa - Overdistended Bladder

Bladder

c

Cervical canal

Placental Edge by U/S and Route of Delivery

• >2 cm os - placenta edge = safe for vaginal delivery

• <1cm os - placenta edge - Cesarean delivery

• 1-2 cm = may be able to deliver vaginal

– Dawson et al Jultrasound Medicine 1996

Ultrasound’s Role

• Previa = usually definitive except in very low lying posterior placentas in the obese patient

• Abruption - definitive diagnosis is not possible

• Transvaginal Scanning is safe in the bleeding patient

Clinical Signs and Clinical Signs and SymptomsSymptoms

• Painless Bleeding = Previa

• Painful Bleeding = Abruption

• Painless Fetal Bleeding = Vasa Previa

Initial managementInitial management

• 1) ABC’s1) ABC’s– Amount of bleeding noted is Amount of bleeding noted is

unreliableunreliable

• 2) Fetal Well Being2) Fetal Well Being• 3) No Vaginal Exams3) No Vaginal Exams

– Until you know where the Until you know where the placenta is!placenta is!

• 4) Ultrasound4) Ultrasound

Fetal/Neonatal Considerations

• Gestational Age of Fetus dictates local of care

• SGA/Prematurity are major problems

• Communication with consultants is key!

Cesarean Sections and Previas

• Pre-op Scan• Patients with Previas

undergoing C-Section– Bleed More– Require More Blood

Transfusion– Require More C-

Hysterectomies– Placenta accreta may

accompany 10%• Bladder invasion may be

associated with– DIC and massive hemorrhage

Treatment Placenta Previa

• With no active bleeding– Expectant management

– No intercourse, digital exam

– Rescan after 30 weeks

• With late pregnancy bleeding– Assess overall status, circulatory stability

– Full dose Rhogam if Rh -

– Consider maternal transfer if premature

– May need corticosteroids, tocolysis, amniocentesis

Expectant Management

• May discharge home if stable after 72 hours of inpatient observation.

• Reduces stay in hospital by average of 14 days.

• No increase in– Hemorrhage– Need for transfusion– Poor maternal or neonatal outcomes

Tocolytics in Placenta Previa

• Greatest morbidity and mortlity related to prematurity.

• Tocolytics can add an additional 11 days to pregnancy.– Allows for administration of corticosteroids– No increase in maternal or fetal complications– Increase birth weights average of 320 grams

Double Set-up Exam: digital exam in OR with ability to do immediate CD

• Appropriate only in marginal (anterior) 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 Persistant bleeding– Mature fetus

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

Epidemiology of Abruption*

• Occurs in 1-2% of all pregnancies• Risk Factors

– Hypertensive diseases of pregnancy– Smoking or substance abuse*– Trauma*– Overdistension of the Uterus*– History of Previous Abruption*– Unexplained elevation of MSAFP– Placental insufficiency– Maternal Thrombophilia/Metabolic abnormalities

Abruptions and Trauma

• Can occur with blunt abdominal trauma and rapid deceleration without direct trauma

• Complications include prematurity, growth restriction and stillbirth

• Fetal evaluation after trauma– Increased use of FHR monitoring may decrease

mortality

Bleeding from Abruption

• Externalized hemorrhage

• Bloody amniotic fluid

• Retroplacental clot– 20% occult

– “uteroplacental apoplexy or Couvelaire uterus

• Look for consumptive coagulopathy

““Uteroplacental apoplexy or Couvelaire” uterusUteroplacental apoplexy or Couvelaire” uterus

Cigarette Smoking as Risk factor

• Nova Scotia Registry of 87, 184 pregnancies

• 33% smoked• 2.05 Relative Risk of Abruption• 1.75 Relative Risk of Previa• No dose effect noted

• Anath AmJ of Epidemiology 1996

Cocaine/Metamphetamine

• Associated with – chorionic villous

hemorrhage– Villous edema– Even in the absence of

clinical abruption placenta

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/drugs)• Membrane rupture

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

Fetal/Uterine Monitor in an Abruption

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

Placental Abruption

Hemorrhage isoechoic with placenta Hematoma retroplacental

Abruption - Retroplacental Hematoma

Retro placental hematoma day1 7 days later

False Abruption? Contraction Mimicking Abruption

Contraction

No Contraction 30 minutes later

Placenta Lakes

Subchorionic Placental Lake

Doppler revealing flow through the lake

Laboratory-Abruption

• Complete blood count• Type and Rh• Coagulation tests + “Clot test”• Kleihauer-Betke test not

diagnostic, but useful to determine Rhogam dose

• Pre-eclampsia labs, if indicated• Consider urine drug screen

Sher’s Classification

Grade IMild, often retroplacental clot identified at delivery

Grade IITense, tender abdomen and live fetus

Grade III

-IIIA

-IIIB

With fetal demise

-without coagulopathy (2/3)

-with coagulopathy (1/3)

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 hemotocrit > 30%

• Prepare for neonatal resuscitation

Treatment - Grade III Abruption

• Assess mother for hemodynamic and coagulation status

• Vigorous replacement of fluid and blood products

• Vaginal delivery preferred, unless severe hemorrhage

Coagulopathy with Abruption

• Occurs in 1/3 of Grade III abruptions

• Usually not seen if live fetus

• Etiologies: consumption, DIC

• Administer platelets, FFP

• Give Factor VIII if severe

Epidemiology of Uterine Rupture*

• Occult dehiscence vs.. symptomatic rupture• .03%-.08% of all women• .03%-1.7% of all women with uterine scar• Previous cesarean incision most common

reason for scar disruption• Other causes: previous uterine curettage or

perforation, inappropriate oxytocin usage, trauma, drugs*

Risk Factors - Uterine Rupture*

• Previous Uterine Surgery*

• Congenital Uterine Anomalies

• Uterine Overdistension*

• Gestational Trophoblastic Disease

• Adenomyosis• Fetal Anomaly• Vigorous Uterine

Pressure• Difficult Placental

Removal• Placenta Increta or

Percreta (US/MRI)

During labor or delivery

Extension of Transverse

Scar

Midline Classical Rupture

CatastrophicRupture

Uterine Scar Disruption

Morbidity with Uterine Rupture

• Maternal– Hemorrhage with anemia– Bladder rupture– Hysterectomy– Maternal Death

• Fetal– Respiratory distress– Hypoxia– Acidemia– Neonatal death

Patient History -Uterine Rupture*

• Vaginal Bleeding• Pain• Cessation of contractions*• Absences FHR• Loss of Station• Palpable fetal parts through

maternal abdomen• Profound maternal tachycardia

and hypotension

Uterine Rupture• Sudden deterioration of FHR pattern is a

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

Vasa Previa

Bridging vessels

Vasa Previa

• Rarest cause of hemorrhage• Onset with membrane rupture• Blood Loss is fetal, with 56% mortality (3%)• Associated with placenta previa, velamentous

insertion of the cord, bilobed/succenturiate lobe, or IVF

• Antepartum diagnosis– Amnioscopy– Color doppler ultrasound– Palpate vessels during vaginal examination

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 hour delay prohibits its use

Modified Apt Test

• Several cc’s of blood from vagina

• Mix with Tap water

• Centrifuge

• Mix supernatant with NaOH

• Read Color in Two minutes

• Fetal = pink

• Adult = brown

Management Vasa Previa

• Immediate Cesarean Delivery if fetal heart non-reassuring

• Administer normal saline 10-20 cc/kg bolus to newborn, if found to be in shock after delivery

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!

Transvaginal Predictive Value

• TVS Overlap of 10 mm or more @ 15-20 weeks predictive 100% previa at term

– Lauria US ObGyn Nov 1996

• TVS Overlap of 15 mm @ 12-16 weeks predictive at birth 5.1 %

– Taipale ObGyn 1997

Risk factors for Abruptions

• Younger Women RR 1.4– Parity > 3 RR 10– May reflect effects of close pregnancy

spacing

• Previous Abruption RR 10• Chronic Hypertension• Preeclampsia RR 1.7• PROM RR 3.0