Abruptio Placentae

Author: Shad H Deering, MD, Clinical Assistant Professor, Department of Obstetrics and Gynecology, University of Washington; Medical Director, Andersen Simulation Center, Madigan Army Medical Center

Introduction

Background

Abruptio placentae is defined as the premature separation of the placenta from the uterus. Patients with abruptio placentae typically present with bleeding, uterine contractions, and fetal distress. A significant cause of third-trimester bleeding associated with both fetal and maternal morbidity and mortality, abruptio placentae must be considered whenever bleeding is encountered in the second half of pregnancy.

Pathophysiology

Hemorrhage into the decidua basalis occurs as the placenta separates from the uterus. Vaginal bleeding usually follows, although the presence of a concealed hemorrhage in which the blood pools behind the placenta is possible.

If the bleeding continues, fetal and maternal distress may develop. Fetal and maternal death may occur if appropriate interventions are not undertaken. The primary cause of placental abruption is usually unknown, but multiple risk factors have been identified.

Frequency

United States

The frequency of abruptio placentae in the United States is approximately 1%, and a severe abruption leading to fetal death occurs in 0.12% of pregnancies (1:830).

Mortality/Morbidity

Maternal or fetal mortality or morbidity may occur.

If an abruption occurs, the risk of perinatal mortality is reported as 119 per 1,000 people in the United States, but this can depend on the extent of the abruption and the gestational age of the fetus. This rate is higher in patients with a significant smoking history. Fetal morbidity is caused by the insult of the abruption itself and by issues related to prematurity when early delivery is required to alleviate maternal or fetal distress.

Currently, placental abruption is responsible for approximately 6% of maternal deaths. Maternal and fetal complications include issues related to (1) cesarean delivery, (2) hemorrhage/coagulopathy, and (3) prematurity, described as follows:

  • Cesarean delivery: Cesarean delivery is often necessary if the patient is far from her delivery date or if significant fetal compromise develops. If significant placental separation is present, the fetal heart rate tracing typically shows evidence of fetal decelerations and even persistent fetal bradycardia. A cesarean delivery may be complicated by infection, additional hemorrhage, the need for transfusion of blood products, injury of the maternal bowel or bladder, and/or hysterectomy for uncontrollable hemorrhage. In rare cases, death occurs.
  • Hemorrhage/coagulopathy: Disseminated intravascular coagulation (DIC) may occur as a sequela of placental abruption. Patients with a placental abruption are at higher risk of developing a coagulopathic state than those with placental previa. The coagulopathy must be corrected to ensure adequate hemostasis in the case of a cesarean delivery.
  • Prematurity: Delivery is required in cases of severe abruption or when significant fetal or maternal distress occurs, even in the setting of profound prematurity. In some cases, immediate delivery is the only option, even before the administration of corticosteroid therapy in these premature infants. All other problems and complications associated with a premature infant are also possible.

Race

Placental abruption is more common in African American women than in either white or Latin American women. However, whether this is the result of socioeconomic, genetic, or combined factors remains unclear.

Sex

This condition is observed only in pregnancy.

Age

An increased risk of placental abruption has been demonstrated in patients younger than 20 years and those older than 35 years.

Clinical

History

Symptoms may include vaginal bleeding, contractions, abdominal tenderness, and decreased fetal movement. Eliciting any history of trauma, such as assault, abuse, or motor vehicle accident, is important. A quick review of the patient's prenatal course, such as a known history of placenta previa, may help lead to the correct diagnosis. The patient should also be asked if she has had a placental abruption in a previous pregnancy. Questioning the patient about cocaine abuse, hypertension, trauma, or tobacco abuse is also crucial.

  • Vaginal bleeding
    • Vaginal bleeding is present in 80% of patients diagnosed with placental abruptions.
    • Bleeding may be significant enough to jeopardize both fetal and maternal health in a relatively short period.
    • Remember that 20% of abruptions are associated with a concealed hemorrhage and the absence of vaginal bleeding does not exclude a diagnosis of abruptio placentae.
  • Contractions/uterine tenderness
    • Contractions and uterine hypertonus are part of the classic triad observed with placental abruption.
    • Uterine activity is a sensitive marker of abruption and, in the absence of vaginal bleeding, should suggest the possibility of an abruption, especially after some form of trauma or in a patient with multiple risk factors.
  • Decreased fetal movement
    • This may be the presenting complaint.
    • Decreased fetal movement may be due to fetal jeopardy or death.

Physical

The physical examination of a patient who is bleeding must be targeted at determining the origin of the hemorrhage. Simultaneously, the patient must be stabilized quickly. With placental abruption, a relatively stable patient may rapidly progress to a state of hypovolemic shock.

  • Vaginal bleeding
    • Bleeding may be profuse and come in "waves" as the patient's uterus contracts.
    • A fluid the color of port wine may be observed when the membranes are ruptured.
  • Contractions/uterine tenderness
    • Uterine contractions are a common finding with placental abruption.
    • Contractions progress as the abruption expands, and uterine hypertonus may be noted.
    • Contractions are painful and palpable.
    • Uterine hyperstimulation may occur with little or no break in uterine activity between contractions.
  • Shock
    • Patients may present with hypovolemic shock, with or without vaginal bleeding, because a concealed hemorrhage may be present.
    • As with any hypovolemic condition, blood pressure drops as the pulse increases, urine output falls, and the patient progresses from an alert to an obtunded state as the condition worsens.
  • Absence of fetal heart sounds: This occurs when the abruption progresses to the point that the fetus dies.
  • Signs of possible fetal jeopardy
    • Fetal bradycardia is prolonged.
    • Repetitive, late decelerations are present.
    • Short-term variability is decreased.
  • Fundal height: This may increase rapidly because of an expanding intrauterine hematoma.
  • Important note: Do not perform a digital examination on a pregnant patient with vaginal bleeding without first ascertaining the location of the placenta. Before a pelvic examination can be safely performed, an ultrasonographic examination should be performed to exclude placenta previa. If placenta previa is present, a pelvic examination, either with a speculum or with bimanual examination, may initiate profuse bleeding.

Causes

While multiple risk factors are associated with abruptio placentae, only a few events have been closely linked to this condition, including the following:

  • Cigarette smoking/tobacco abuse
    • Cigarette smoking increases a patient's overall risk of placental abruption.
    • A prospective cohort study showed the risk of abruption to be increased by 40% for each year of smoking prior to pregnancy.
    • In addition to the increased risk of abruption caused by tobacco abuse, the perinatal mortality rate of infants born to women who smoke and have an abruption is increased.
  • Cocaine (powder or crack) abuse
    • The hypertension and increased levels of catecholamines caused by cocaine abuse are thought to be responsible for a vasospasm in the uterine blood vessels that causes placental separation and abruption. However, this hypothesis has not been definitively proven.
    • The rate of abruption in patients who abuse cocaine has been reported to be approximately 13-35% and may be dose-dependent.
  • Trauma
    • Abdominal trauma is a major risk factor for placental abruption.
    • Motor vehicle accidents often cause abdominal trauma. The lower seat belt should extend across the pelvis, not across the mid abdomen, where the fetus is located.
    • Trauma may also be due to domestic abuse or assault, both of which are underreported.
  • Thrombophilia
    • Some literature supports the association of specific thrombophilias, such as factor V Leiden mutation, prothrombin gene mutation (A20210 mutation), hyperhomocysteinemia, activated protein C resistance, antithrombin III deficiency, and anticardiolipin immunoglobulin G antibodies, and this risk may be independent of the presence of preeclampsia. The presence of a thrombophilia may also influence the severity of the abruption.
    • Note, however, that other literature does not support an association between thrombophilias and placental abruption. If a patient with a placental abruption is screened and is positive for a thrombophilia she should be offered treatment with heparin and aspirin during the next pregnancy.
  • Other notable risk factors include the following:
    • Previous placental abruption
    • Chorioamnionitis
    • Prolonged rupture of membranes (24 h or longer)
    • Preeclampsia
    • Hypertension
    • Maternal age of 35 years or older
    • Male fetal sex
    • Low socioeconomic status
    • Elevated second trimester maternal serum alpha-fetoprotein (associated with up to a 10-fold increased risk of abruption)

Differential Diagnoses

Placenta Previa
Preterm Labor

Other Problems to Be Considered

Labor with bloody show
Vasa previa
Vaginal trauma
Malignancy (rare)

Workup

Laboratory Studies

  • No laboratory studies have been shown to definitively help with the differential diagnosis of abruptio placentae; however, multiple laboratory studies may be helpful in the management of this problem.
  • CBC count
    • A CBC count can help determine the patient's current hemodynamic status, but findings are not reliable for estimating acute blood loss.
    • In an acute hemorrhage, the fall in hematocrit value lags several hours behind the bleeding and may be falsely decreased by the administration of crystalloid fluids during resuscitation.
  • Fibrinogen
    • Pregnancy is associated with hyperfibrinogenemia; therefore, modestly depressed fibrinogen levels may represent significant coagulopathy. A fibrinogen level of less than 200 mg/dL suggests that the patient has a severe abruption.
    • The goal should be to keep the fibrinogen level above 100 mg/dL, which can be accomplished via transfusion of fresh frozen plasma or cryoprecipitate, as necessary.
  • Prothrombin time/activated partial thromboplastin time
    • Some form of DIC is present in up to 20% of patients with severe abruptions.
    • Because many of these patients may require cesarean delivery, knowing a patient's coagulation status is imperative.
  • Blood urea nitrogen/creatinine
    • The hypovolemic condition brought on by a significant abruption also affects renal function.
    • The condition usually self-corrects without significant residual dysfunction if fluid resuscitation is timely and adequate.
  • Kleihauer-Betke test
    • Findings help detect fetal red blood cells in the maternal circulation.
    • If the abruption is significant, inadvertent transfusion of fetal blood into the maternal circulation may occur. In women who are Rh-negative, this fetal-to-maternal transfusion may lead to isoimmunization of the mother to Rh factor. Kleihauer-Betke test findings help determine the volume of fetal blood transfused into the maternal circulation.
    • All patients who are D-negative should receive Rho (D) immune globulin (RhoGAM) after significant trauma. Kleihauer-Betke test findings may help determine the appropriate dosage of Rho (D) immune globulin in cases of significant fetal-maternal hemorrhage.
  • Blood type: The patient should have her blood typed and at least 2 units of packed red blood cells crossmatched in the event she requires a transfusion.
  • Rh type: The blood Rh type is important to determine because patients who are Rh-negative require Rh immune globulin in order to prevent isoimmunization, which could affect future pregnancies.
  • Thrombophilia workup
    • While this is not of immediate concern or helpful in stabilizing the acute event, patients with an early or severe abruption may be tested for genetic thrombophilias given their possible association with this complication.
    • Laboratory studies should evaluate for the following:
      • Factor V Leiden mutation
      • Prothrombin gene (A20210) mutation
      • Antithrombin III deficiency
      • Protein C and protein S deficiencies
      • Fasting homocysteine level
      • Anticardiolipin antibodies
      • Activated protein C resistance

Imaging Studies

  • Ultrasonography
    • Ultrasonography is a readily available and important imaging modality for assessing bleeding in pregnancy.
    • The quality and sensitivity of ultrasonography in detecting placental abruptions has improved significantly; however, it is not a sensitive modality for this purpose—findings are positive in only 25% of cases confirmed at delivery and the negative predictive value is low at around 50%.
    • In addition, there does not appear to be any clinical difference in presentation between women who have an abruption seen on ultrasound and those who do not.
    • Ultrasonographic studies help to quickly diagnose placenta previa as the etiology of bleeding, if present.
    • Placental abruption shows as a retroplacental clot on an ultrasound image, but not all abruptions are ultrasonographically detectable.
    • In the acute phase, a hemorrhage is generally hyperechoic, or even isoechoic, compared with the placenta; a hemorrhage does not become hypoechoic for nearly a week.
    • Ultrasonography can help exclude other causes of third-trimester bleeding. Possible findings consistent with an abruption include (1) retroplacental clot (ie, hyperechoic to isoechoic in the acute phase, changing to hypoechoic within a wk), (2) concealed hemorrhage, or (3) expanding hemorrhage.

Other Tests

  • Nonstress test
    • External fetal monitors often reveal fetal distress, as evidenced by late decelerations, fetal bradycardia, or decreased beat-to-beat variability.
    • An increase in the uterine resting tone may also be noticed, along with frequent contractions that may progress to uterine hyperstimulation.
  • Biophysical profile
    • A biophysical profile (BPP) can be used to help evaluate patients with chronic abruptions who are being managed conservatively.
    • A BPP score less than 6 (maximum of 10) may be an early sign of fetal compromise.
    • A modified BPP (nonstress test with amniotic fluid index) is sometimes used for monitoring in this situation.

Procedures

Any procedures that may be required (ie, continuous monitoring of the fetal heart rate tracing, vaginal delivery, cesarean section) will be dictated by both the gestational age and the overall status of the fetus. This is discussed in more detail below.

Histologic Findings

After delivery of the placenta, a retroplacental clot may be noted. Another possible finding involves extravasation of blood into the myometrium, which produces a purple discoloration of the uterine serosa. This phenomenon is known as a Couvelaire uterus.

Treatment

Medical Care

Inpatient admission is required if abruptio placentae is considered likely.

  • Procedures
    • Begin continuous external fetal monitoring for both the fetal heart rate and contractions.
    • Obtain intravenous access using 2 large-bore intravenous lines.
    • Institute crystalloid fluid resuscitation for the patient.
    • Type and crossmatch blood.
    • Begin a transfusion if the patient is hemodynamically unstable after fluid resuscitation.
    • Correct coagulopathy, if present.
    • Administer Rh immune globulin if the patient is Rh-negative.
  • Vaginal delivery
    • This is the preferred method of delivery for a fetus that has died secondary to placental abruption.
    • The ability of the patient to undergo vaginal delivery depends on her remaining hemodynamically stable.
    • Delivery is usually rapid in these patients secondary to increased uterine tone and contractions.

Surgical Care

  • Cesarean delivery
    • Cesarean delivery is often necessary for both fetal and maternal stabilization.
    • While cesarean delivery facilitates rapid delivery and direct access to the uterus and its vasculature, it can be complicated by the patient's coagulation status. Because of this, a vertical skin incision, which has been associated with less blood loss, is often used when the patient appears to have DIC.
    • The type of uterine incision is dictated by the gestational age of the fetus, with a vertical or classic uterine incision often being necessary in the preterm patient.
    • If hemorrhage cannot be controlled after delivery, a cesarean hysterectomy may be required to save the patient's life.
    • Before proceeding to hysterectomy, other procedures, including correction of coagulopathy, ligation of the uterine artery, administration of uterotonics (if atony is present), packing of the uterus, and other techniques to control hemorrhage, may be attempted.
  • ICU: If the patient is hemodynamically unstable, either before or after delivery, invasive monitoring in an ICU may be required.

Consultations

  • Maternal-fetal medicine specialist
    • If a mild abruption is diagnosed or the diagnosis is questionable, a maternal-fetal medicine (MFM) specialist should be consulted.
    • In the case of a preterm fetus in which tocolysis is considered likely, consulting an MFM specialist may be prudent.
  • Pediatricians or neonatal intensive care specialists should be consulted if the fetus is considered viable, usually at 24 weeks' gestation, and delivery is anticipated.

Diet

The patient should be restricted to nothing by mouth (NPO) if emergent delivery is a possibility.

Activity

Preterm patients diagnosed with a chronic abruption may be started on a modified bedrest regimen and monitored closely for any signs of maternal or fetal distress that could necessitate delivery. Again, consultation with MFM specialists is advised for conservative management of abruptio placentae.

Medication

Tocolysis is considered controversial in the management of placental abruption and is considered only in patients (1) who are hemodynamically stable, (2) in whom no evidence of fetal jeopardy exists, and (3) in whom a preterm fetus may benefit from corticosteroids or delay of delivery.

Even in patients meeting these criteria, consultation with an MFM specialist is important. Tocolysis must be undertaken with caution because maternal or fetal distress can develop rapidly. In general, either magnesium sulfate or nifedipine (but not both) is used for tocolysis and beta-sympathomimetic agents are avoided, as the latter may cause significant undesirable cardiovascular effects, such as tachycardia, which may mask clinical signs of blood loss in these patients.

Tocolytics

May allow for effective administration of glucocorticoids to the preterm fetus to accelerate fetal lung maturation. In chronic abruption, may also help delay delivery to a gestational age when complications of prematurity are less severe.

 

Nifedipine (Adalat, Procardia)

A calcium channel blocker. The theory behind use as tocolytic is that by blocking influx of calcium into uterine muscle cells, it will decrease contractions, which are dependent on calcium.

Adult

Loading dose: 10 mg PO q20min for up to 4 doses
Maintenance dose: 10 mg PO q4-6 h

Pediatric

Not established

Coadministration with magnesium sulfate has potential to act in a synergistic manner with nifedipine and enhance the hypotensive effects; fentanyl and alcohol may increase hypotensive effects; calcium channel blocker may increase cyclosporine levels; H2 blockers (cimetidine), erythromycin, nafcillin, and azole antifungals may increase toxicity (avoid combination or monitor closely); carbamazepine may reduce bioavailability (avoid this combination); rifampin may decrease levels (monitor and adjust dose of calcium channel blocker)

Hypersensitivity to nifedipine; evidence of an acute myocardial infarction

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Potential side effects include hypotension, dizziness, nausea, pulmonary edema, reflex tachycardia; may cause lower extremity edema; allergic hepatitis have occurred but is rare

 

Magnesium sulfate

DOC for tocolysis in patients with placental abruption.

Adult

Initial dose: 4-6 g IV bolus over 20 min
Maintenance dose: 2-4 g/h IV, titrated prn to suppress contractions

Pediatric

Not established

Follow-up

Further Inpatient Care

Admit the patient for testing and possible delivery.

Inpatient & Outpatient Medications

  • Prenatal vitamins
  • Iron supplements
  • Stool softeners if the patient is hemodynamically stable and is kept in an inpatient setting for monitoring

Transfer

  • Transfer to an ICU may be necessary, before or after delivery, if shock develops that requires invasive central monitoring or if operative complications are encountered.
  • Transfer to a facility with a neonatal ICU is needed if the fetus is preterm and appropriate facilities are not available. This should be accomplished after delivery if delivery is required to stabilize the mother.

Deterrence/Prevention

  • Elimination of correctable risk factors can decrease the risk of recurrence in subsequent pregnancies.
  • Two of the most notable correctable factors are smoking and cocaine abuse. Education about the risks of these behaviors and about cessation or rehabilitation programs may help prevent future abruptions.
  • If a patient was abused, preventing further abuse is an important consideration.
  • Because of the potential association with thrombophilias, a patient found to have a thrombophilia who had a severe or early abruption, especially with death of the fetus, is usually treated with heparin anticoagulation therapy during the following pregnancy and for 6 weeks' postpartum, though, at present, little evidence has demonstrated that this measure decreases the risk of recurrence.

Complications

  • Fetal
    • Death
    • Issues related to prematurity
  • Maternal
    • Death
    • Transfusion-related morbidity
    • Classic cesarean delivery with need for repeat cesarean deliveries
    • Hysterectomy

Prognosis

  • The risk of recurrence of abruptio placentae is reportedly 4-12%. If the patient has abruptio placentae in 2 consecutive pregnancies, the risk of recurrence rises to 25%.
  • If the abruption was severe and resulted in the death of the fetus, the risk of a recurrent abruption and fetal demise is 7%.

Patient Education

  • Educate patients about reversible risk factors, especially smoking, before further pregnancies.
  • Question the patient regarding possible trauma from abuse.

Miscellaneous

Medicolegal Pitfalls

  • Failure to recognize signs and symptoms of abruptio placentae, or failure to intervene in a timely manner, can lead to medical/legal problems.
  • As with any case in obstetrics, the possibility for litigation always exists. Controversial decisions made regarding placental abruption, especially when tocolysis is considered, should be made after consultation with an MFM specialist.

References

  1. Abu-Heija A, al-Chalabi H, el-Iloubani N. Abruptio placentae: risk factors and perinatal outcome. J Obstet Gynaecol Res . Apr 1998;24(2):141-4. [Medline] .

  2. Alfirevic Z, Roberts D, Martlew V. How strong is the association between maternal thrombophilia and adverse pregnancy outcome? A systematic review. Eur J Obstet Gynecol Reprod Biol . Feb 10 2002;101(1):6-14. [Medline] .

  3. American College of Obstetricians and Gynecologists. ACOG technical bulletin. Preterm labor. Number 206--June 1995 (Replaces No. 133, October 1989). Int J Gynaecol Obstet . Sep 1995;50(3):303-13. [Medline] .

  4. Ananth CV, Smulian JC, Vintzileos AM. Incidence of placental abruption in relation to cigarette smoking and hypertensive disorders during pregnancy: a meta-analysis of observational studies. Obstet Gynecol . Apr 1999;93(4):622-8. [Medline] .

  5. Ananth CV, Wilcox AJ. Placental abruption and perinatal mortality in the United States. Am J Epidemiol . Feb 15 2001;153(4):332-7. [Medline] .

  6. Ananth CV, Savitz DA, Luther ER. Maternal cigarette smoking as a risk factor for placental abruption, placenta previa, and uterine bleeding in pregnancy. Am J Epidemiol . Nov 1 1996;144(9):881-9. [Medline] .

  7. Ananth CV, Savitz DA, Bowes WA Jr, Luther ER. Influence of hypertensive disorders and cigarette smoking on placental abruption and uterine bleeding during pregnancy. Br J Obstet Gynaecol . May 1997;104(5):572-8. [Medline] .

  8. Anteby EY, Musalam B, Milwidsky A, et al. Fetal inherited thrombophilias influence the severity of preeclampsia, IUGR and placental abruption. Eur J Obstet Gynecol Reprod Biol . Mar 15 2004;113(1):31-5. [Medline] .

  9. Clark SL. Placentae previa and abruptio placentae. In: Creasy RK, Resnik R, eds. Maternal Fetal Medicine . 5th ed. Philadelphia, Pa: WB Saunders; 2004:715.

  10. Facchinetti F, Marozio L, Grandone E, et al. Thrombophilic mutations are a main risk factor for placental abruption. Haematologica . Jul 2003;88(7):785-8. [Medline] .

  11. Foley MR, Strong TH Jr, Foley MR, eds. Placental Abruption. In: Obstetric Intensive Care: A practical manual . First ed. Philadelphia, Pa: WB Saunders; 1997:35-9.

  12. Gabbe SG, Niebyl JR, Simpson JL, eds. Abruptio placenta. In: Obstetrics - Normal and Problem Pregnancies . 3rd ed. New York, NY: Churchill Livingstone; 1996:505-10.

  13. Glantz C, Purnell L. Clinical utility of sonography in the diagnosis and treatment of placental abruption. J Ultrasound Med . Aug 2002;21(8):837-40. [Medline] .

  14. Hoskins IA, Friedman DM, Frieden FJ. Relationship between antepartum cocaine abuse, abnormal umbilical artery Doppler velocimetry, and placental abruption. Obstet Gynecol . Aug 1991;78(2):279-82. [Medline] .

  15. Kramer MS, Usher RH, Pollack R. Etiologic determinants of abruptio placentae. Obstet Gynecol . Feb 1997;89(2):221-6. [Medline] .

  16. Kujovich JL. Thrombophilia and pregnancy complications. Am J Obstet Gynecol . Aug 2004;191(2):412-24. [Medline] .

  17. Kupferminc MJ, Eldor A, Steinman N, et al. Increased frequency of genetic thrombophilia in women with complications of pregnancy. N Engl J Med . Jan 7 1999;340(1):9-13. [Medline] .

  18. Lockwood CJ. Inherited thrombophilias in pregnant patients: detection and treatment paradigm. Obstet Gynecol . Feb 2002;99(2):333-41. [Medline] .

  19. Misra DP, Ananth CV. Risk factor profiles of placental abruption in first and second pregnancies: heterogeneous etiologies. J Clin Epidemiol . May 1999;52(5):453-61. [Medline] .

  20. No authors listed. Correction: Increased Frequency of Genetic Thrombophilia in Women with Complications of Pregnancy. N Engl J Med . Jul 29 1999;341(5):384. [Medline] .

  21. Oyelese Y, Ananth CV. Placental abruption. Obstet Gynecol . Oct 2006;108(4):1005-16.

  22. Pritchard JA, Mason R, Corley M, Pritchard S. Genesis of severe placental abruption. Am J Obstet Gynecol . Sep 1 1970;108(1):22-7. [Medline] .

  23. Pritchard JA, Cunningham FG, Pritchard SA, Mason RA. On reducing the frequency of severe abruptio placentae. Am J Obstet Gynecol . Nov 1991;165(5 Pt 1):1345-51. [Medline] .

  24. Rana A, Sawhney H, Gopalan S. Abruptio placentae and chorioamnionitis-microbiological and histologic correlation. Acta Obstet Gynecol Scand . May 1999;78(5):363-6. [Medline] .

  25. Rasmussen S, Irgens LM, Bergsjo P. The occurrence of placental abruption in Norway 1967-1991. Acta Obstet Gynecol Scand . Mar 1996;75(3):222-8. [Medline] .

  26. Raymond EG, Mills JL. Placental abruption. Maternal risk factors and associated fetal conditions. Acta Obstet Gynecol Scand . Nov 1993;72(8):633-9. [Medline] .

Fri, 23 Jul 2010 @00:18

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