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Placenta Previa

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Placenta Previa

para>Do not perform digital cervical exam in any woman with a complaint of bleeding until placental position has been verified.

Initial Tests (lab, imaging)

Recombinant factor VII is an alternative blood product for DIC when fresh frozen plasma and cryoprecipitate fail. ‚

Admission Criteria/Initial Stabilization

No restrictions once stable; NPO if delivery possible ‚

www.nlm.nih.gov/medlineplus/ency/article/000900.htm ‚

11 Rao ‚ KP, Belogolovkin ‚ V, Yankowitz ‚ J, et al. Abnormal placentation: evidence-based diagnosis and management of placenta previa, placenta accreta, and vasa previa. Obstet Gynecol Surv. 2012;67(8):503 " “519.22 American College of Obstetricians and Gynecologists. ACOG Committee Opinion No. 560: medically indicated late-preterm and early-term deliveries. Obstet Gynecol. 2013;121(4):908 " “910.

Careful sterile speculum exam can be performed to evaluate for vaginal/cervical source of bleeding.

Evaluate for rupture of membranes as cause for bleeding.

DIFFERENTIAL DIAGNOSIS

  • Abruptio placentae
  • Vasa previa
  • Labor
  • Vaginal infections

DIAGNOSTIC TESTS & INTERPRETATION

  • Transvaginal ultrasound is gold standard to identify placental position accurately (1)[A].
  • Transabdominal US may be associated with incorrect diagnosis in 25% of cases (1).
  • MRI if placenta accreta or percreta is suspected
  • Fetal heart monitoring
  • Maternal blood type and antibody screen
  • CBC
  • Cross-match for 2 to 4 units if heavy bleeding
  • Coagulation labs including fibrinogen, prothrombin time (PT), and partial thromboplastin time (PTT) if massive blood loss or abruption is suspected.
  • Kleihauer-Betke test: Positive test indicates fetal " “maternal transfusion may be present and can determine Rho(D) immunoglobulin dosing in Rh-negative patients.
  • Repeat US to look for resolution.
  • Assess CBC in cases of large blood loss.

TREATMENT

GENERAL MEASURES

  • Avoid vaginal intercourse and strenuous exercise after 20 weeks.
  • Avoid vaginal exams, sexual intercourse, douching, or other vaginal manipulation.
  • Rh-negative women should receive 300 Ž Ľg Rho(D) immunoglobulin (RhoGAM).
  • Supportive therapy
  • Bed rest is not necessary.

MEDICATION

  • Antenatal corticosteroids for symptomatic women 23 to 34 weeks to enhance fetal pulmonary maturity
  • Magnesium sulfate for neuroprotection in preterm patients 24 to 32 weeks
  • Oxygen supplementation if needed
  • Adequate IV access via large-bore catheters
  • Aggressive IV fluids/blood products as needed: fresh frozen plasma, platelets, and packed RBCs
  • Use of tocolytics is controversial (1).

ISSUES FOR REFERRAL

  • Maternal " “fetal medicine consult for delivery decisions regarding stable patients
  • Neonatal ICU team should be alerted for high-risk delivery and consulted for preterm delivery.
  • Appropriate interdisciplinary planning with blood bank, anesthesia, nursing staff in anticipation of placenta previa delivery
  • Hospitals with obstetric units should consider massive transfusion protocols and staff training.

ADDITIONAL THERAPIES

SURGERY/OTHER PROCEDURES

  • Timing of deliveryDelivery recommended between 36 0/7 and 37 6/7 weeks without documentation of fetal lung maturity by amniocentesis (2)[C]If accreta, increta, or percreta is suspected, may delivery between 34 0/7 and 35 6/7 weeks (2)[C].Emergent delivery should occur if (i) vaginal bleeding for nonreassuring fetal heart tracing, (ii) life-threatening maternal hemorrhage, or (iii) active labor.
  • Route of deliveryCesarean delivery always indicated in scenario of complete previa and a viable fetusReasonable for vaginal delivery if the placenta is > 20 mm from the internal os in the case of low-lying placenta.Emergent delivery should occur if (i) vaginal bleeding for nonreassuring fetal heart tracing, (ii) life-threatening maternal hemorrhage, or (iii) active labor.
  • Delivery recommended between 36 0/7 and 37 6/7 weeks without documentation of fetal lung maturity by amniocentesis (2)[C]
  • If accreta, increta, or percreta is suspected, may delivery between 34 0/7 and 35 6/7 weeks (2)[C].
  • Emergent delivery should occur if (i) vaginal bleeding for nonreassuring fetal heart tracing, (ii) life-threatening maternal hemorrhage, or (iii) active labor.
  • Cesarean delivery always indicated in scenario of complete previa and a viable fetus
  • Reasonable for vaginal delivery if the placenta is > 20 mm from the internal os in the case of low-lying placenta.
  • Emergent delivery should occur if (i) vaginal bleeding for nonreassuring fetal heart tracing, (ii) life-threatening maternal hemorrhage, or (iii) active labor.

INPATIENT CONSIDERATIONS

  • First episode of vaginal bleeding warrants prolonged inpatient monitoring.
  • Symptomatic women often remain hospitalized from their initial or second significant bleed to the time of delivery.
  • Should remain hospitalized until at least 48 hours without bleeding (1)
  • Multiple large bleeds may necessitate admission until scheduled delivery between 34 and 36 weeks, depending on institutional guidelines.
  • May consider transfer to high-risk perinatology service based on patient condition, local services, and concern for accreta
  • Bed rest and NPO until delivery decision made
  • Two large-bore IV sites and IV fluids as needed for resuscitation
  • Continuous fetal heart and contraction monitoring
  • Continuous fetal heart tracing and tocometry
  • Monitor vital signs and pad counts.
  • Demonstration of fetal well-being by fetal heart tracing/biophysical profile
  • Demonstration of maternal hemodynamic stability
  • No active bleeding for >48 hours
  • Proximity of patient to health care facility and patient reliability

ONGOING CARE

FOLLOW-UP RECOMMENDATIONS

  • Repeat US of placenta location if last US was done at <37 weeks ' gestational age.
  • Placentae should be sent for pathologic evaluation.

DIET

PATIENT EDUCATION

PROGNOSIS

  • Low maternal mortality
  • Greatest fetal risk is preterm delivery and associated sequelae.

COMPLICATIONS

  • Peripartum hysterectomyEspecially with associated accreta/increta/percreta
  • Blood transfusion
  • DIC risk is low unless massive bleeding is present.
  • Especially with associated accreta/increta/percreta

REFERENCES

ADDITIONAL READING

  • Belfort ‚ MA. Placenta accreta. Am J Obstet Gynecol. 2010;203(5):430 " “439.
  • Bhide ‚ A, Prefumo ‚ F, Moore ‚ J, et al. Placental edge to internal os distance in the late third trimester and mode of delivery in placenta praevia. BJOG. 2003;110(9):860 " “864.
  • Briggs ‚ GG, Wan ‚ SR. Drug therapy during labor and delivery, part 2. Am J Health Syst Pharm. 2006;63(12):1131 " “1139.
  • Committee on Obstetric Practice. Committee Opinion No. 529: placenta accreta. Obstet Gynecol. 2012;120(1):207 " “211.
  • Downes ‚ KL, Hinkle ‚ SN, Sjaarda ‚ LA, et al. Previous prelabor or intrapartum cesarean delivery and risk of placenta previa. Am J Obstet Gynecol. 2015;212(5):669.e1 " “669.e6.
  • Neilson ‚ JP. Interventions for suspected placenta praevia. Cochrane Database Syst Rev. 2003;(2):CD001998.
  • Oyelese ‚ Y, Smulian ‚ JC. Placenta previa, placenta accreta, and vasa previa. Obstet Gynecol. 2006;107(4):927 " “941.
  • Oyelese ‚ Y. Evaluation and management of low-lying placenta or placenta previa on second-trimester ultrasound. Contemp Ob Gyn. 2010;55(12):30 " “33.
  • Predanic ‚ M, Perni ‚ SC, Baergen ‚ RN, et al. A sonographic assessment of different patterns of placenta previa "migration " ť in the third trimester of pregnancy. J Ultrasound Med. 2005;24(6):773 " “780.
  • Rac ‚ MW, Dashe ‚ JS, Wells ‚ CE, et al. Ultrasound predictors of placental invasion: the placenta accreta index. Am J Obstet Gynecol. 2015;212(3):343.e1 " “343.e7.
  • Robinson ‚ BK, Grobman ‚ WA. Effectiveness of timing strategies for delivery of individuals with placenta previa and accreta. Obstet Gynecol. 2010;116(4):835 " “842.
  • Silver ‚ RM, Landon ‚ MB, Rouse ‚ DJ, et al. Maternal morbidity associated with multiple repeat cesarean deliveries. Obstet Gynecol. 2006;107(6):1226 " “1232.
  • Simon ‚ EG, Fouche ‚ CJ, Perrotin ‚ F. Three-dimensional transvaginal sonography in third-trimester evaluation of placenta previa. Ultrasound Obstet Gynecol. 2013;41(4):465 " “468.
  • Stafford ‚ IA, Dashe ‚ JS, Shivvers ‚ SA, et al. Ultrasonographic cervical length and risk of hemorrhage in pregnancies with placenta previa. Obstet Gynecol. 2010;116(3):595 " “600.

CODES

ICD10

  • O44.10 Placenta previa with hemorrhage, unspecified trimester
  • O44.11 Placenta previa with hemorrhage, first trimester
  • O44.12 Placenta previa with hemorrhage, second trimester
  • O44.00 Placenta previa specified as w/o hemorrhage, unsp trimester
  • O44.03 Placenta previa specified as w/o hemorrhage, third trimester
  • O44.01 Placenta previa specified as w/o hemorrhage, first trimester
  • O44.13 Placenta previa with hemorrhage, third trimester
  • O44.02 Placenta previa specified as w/o hemor, second trimester

ICD9

  • 641.10 Hemorrhage from placenta previa, unspecified as to episode of care or not applicable
  • 641.13 Hemorrhage from placenta previa, antepartum condition or complication
  • 641.11 Hemorrhage from placenta previa, delivered, with or without mention of antepartum condition
  • 641.00 Placenta previa without hemorrhage, unspecified as to episode of care or not applicable
  • 641.01 Placenta previa without hemorrhage, delivered, with or without mention of antepartum condition
  • 641.03 Placenta previa without hemorrhage, antepartum condition or complication

SNOMED

  • Placenta previa (disorder)
  • Placenta previa with hemorrhage - not delivered
  • Placenta previa with hemorrhage
  • Placenta previa without hemorrhage
  • Placenta previa with hemorrhage - delivered

CLINICAL PEARLS

  • Placenta previa is a major cause of vaginal bleeding in the 2nd and 3rd trimesters.
  • Many pregnancies diagnosed with placenta previa will have resolution by term.
  • Do not perform digital cervical exam if placenta previa is being considered, only careful speculum exam.
  • Delivery is almost exclusively by cesarean section.