Risk factors for perinatal mortality in patients admitted to the hospital with the diagnosis of placental abruption

Objective: Placental abruption is a clinical term used when premature separation of the placenta from the uterine wall occurs prior to delivery of the fetus. Hypertension, substance abuse, smoking, intrauterine infection and recent trauma are risk factors for placental abruption. In this study, we sought for clinical factors that increase the risk for perinatal mortality in patients admitted to the hospital with the clinical diagnosis of placental abruption.

Materials and methods: We identified all placental abruption cases managed over the past 6 years at our Center. Those with singleton pregnancies and a diagnosis of abruption based on strict clinical criteria were selected. Eleven clinical variables that had potential for increasing the risk for perinatal mortality were selected, logistic regression analysis was used to identify variables associated with perinatal death.

Results: Sixty-one patients were included in the study with 16 ending in perinatal death (26.2%). Ethnicity, maternal age, gravidity, parity, use of tobacco, use of cocaine, hypertension, asthma, diabetes, hepatitis C, sickle cell disease and abnormalities of amniotic fluid volume were not the main factors for perinatal mortality. Gestational age at delivery, birthweight and history of recent trauma were significantly associated with perinatal mortality. The perinatal mortality rate was 42% in patients who delivered prior to 30 weeks of gestation compared to 15% in patients who delivered after 30 weeks of gestation (p?<?0.05). A three-fold increase in severe trauma was reported in the group of patients with perinatal mortality than in the group with perinatal survivors (25% versus 7%, respectively, p?<?0.05).

Conclusions: In patients admitted to hospital for placental abruption delivery prior to 30 weeks of gestation and a history of abdominal trauma are independent risk factors for perinatal death.     

Placental abruption: epidemiology, risk factors and consequences

Placental abruption, classically defined as a premature separation of the placenta before delivery, is one of the leading causes of vaginal bleeding in the second half of pregnancy. Approximately 0.4-1% of pregnancies are complicated by placental abruption. The prevalence is lower in the Nordic countries (0.38-0.51%) compared with the USA (0.6-1.0%). Placental abruption is also one of the most important causes of maternal morbidity and perinatal mortality. Maternal risks include obstetric hemorrhage, need for blood transfusions, emergency hysterectomy, disseminated intravascular coagulopathy and renal failure. Maternal death is rare but seven times higher than the overall maternal mortality rate. Perinatal consequences include low birthweight, preterm delivery, asphyxia, stillbirth and perinatal death. In developed countries, approximately 10% of all preterm births and 10-20% of all perinatal deaths are caused by placental abruption. In many countries, the rate of placental abruption has been increasing. Although several risk factors are known, the etiopathogenesis of placental abruption is multifactorial and not well understood.     

Placental abruption

Placental abruption complicates about 1% of pregnancies and is a leading cause of vaginal bleeding in the latter half of pregnancy. It is also an important cause of perinatal mortality and morbidity. The maternal effect of abruption depends primarily on its severity, whereas its effect on the fetus is determined both by its severity and the gestational age at which it occurs. Risk factors for abruption include prior abruption, smoking, trauma, cocaine use, multifetal gestation, hypertension, preeclampsia, thrombophilias, advanced maternal age, preterm premature rupture of the membranes, intrauterine infections, and hydramnios. Abruption involving more than 50% of the placenta is frequently associated with fetal death. The diagnosis of abruption is a clinical one, and ultrasonography and the Kleihauer-Betke test are of limited value. The management of abruption should be individualized on a case-by-case basis depending on the severity of the abruption and the gestational age at which it occurs. In cases where fetal demise has occurred, vaginal delivery is preferable. Disseminated intravascular coagulopathy should be managed aggressively. When abruption occurs at or near term and maternal and fetal status are reassuring, conservative management with the goal of vaginal delivery may be reasonable. However, in the presence of fetal or maternal compromise, prompt delivery by cesarean is often indicated. Similarly, abruption at extremely preterm gestations may be managed conservatively in selected stable cases, with close monitoring and rapid delivery should deterioration occur. Most cases of placental abruption cannot be predicted or prevented. However, in some cases, maternal and infant outcomes can be optimized through attention to the risks and benefits of conservative management, ongoing evaluation of fetal and maternal well-being, and through expeditious delivery where appropriate.     

Placenta previa: aggressive expectant management

We report the outcomes of 95 expectantly managed cases of placenta previa; all were diagnosed after 21 weeks' gestation. Patients at risk for preterm delivery because of hemorrhage or preterm labor received aggressive care, including multiple transfusions, volume expansion and tocolytic therapy, and amniotic fluid surfactant determinations, to achieve the goal of delivery at 37 weeks' gestation with mature fetal lung function. We present guidelines for outpatient management and double setup examination prior to delivery. The role of ultrasound in diagnosis (three asymptomatic cases; 13 cases with preterm labor) and serial placental localization to determine the timing, route, and place of delivery is presented. Eighty-six percent of 19 infants born weighing less than 2500 gm were managed expectantly. Hemorrhage was the determinant in delivery timing in 50 cases. All four deaths were neonatal with birth weights less than 2200 gm. This is the lowest perinatal mortality rate (4.2%) published to date. Use of this aggressive approach is particularly suitable for patients cared for in a teritary center.     

Premature rupture of membranes at term in nulliparous women: a hazard?

One hundred five consecutive women with premature rupture of the membranes (PROM) at term were managed expectantly for at least 24 hours. Seventy-six went into spontaneous labor, of whom 38 were augmented with oxytocin. Twenty-nine had labor induced. Subjects who delivered during the same study interval after artificial rupture of the membranes served as controls. There were no statistically significant differences in the frequency of amnionitis, endometritis, cystitis, neonatal infection, low Apgar score, low cord arterial blood pH, instrumental delivery, or cesarean delivery. Morbidity was seen most often in induced labor whether or not the membranes were ruptured for a long time. It is concluded that expectant management of PROM at term does not increase perinatal morbidity.     

Clinical significance of pregnancies with circumvallate placenta

AIM: This study examined the clinical significance of patients complicated by circumvallate placenta in comparison with patients with a normal placenta. METHODS: Data were collected from 139 singleton deliveries complicated by circumvallate placenta and from 7666 unaffected controls managed at Japanese Red Cross Katsushika Maternity Hospital between 2002 and 2005. RESULTS: The incidence of premature delivery, oligohydramnios, non-reassuring fetal status on cardiotocogram, placental abruption and intrauterine fetal death in patients complicated by circumvallate placenta were significantly higher than those in control patients. The odds ratio of placental abruption in patients complicated by circumvallate placenta was 13.1 (95% confidence limits: 5.65-30.2). CONCLUSION: A circumvallate placenta is associated with a higher incidence of serious perinatal complications such as placental abruption.     

Management of the diethylstilbestrol-exposed pregnant patient: a prospective study

Over a 5-year period we have managed 63 diethylstilbestrol-exposed pregnant patients with a standardized protocol requiring weekly cervical examination and decreased physical activity of the patient. Twenty-six patients (42%) underwent a prophylactic cerclage for a history of second-trimester loss or a hypoplastic cervix on initial clinical examination (group I). Thirty-six patients (58%) were followed expectantly (group II). Sixteen patients (44%) in group II demonstrated cervical change and required an emergency cerclage. Twenty-one patients were managed expectantly with no cerclage. The gestational age at delivery for group I was 37.7 +/- 2.80 versus 34.5 +/- 6.9 weeks for patients without a cerclage (p = 0.04). There were no perinatal deaths if a cerclage was performed, whereas there were five deaths (24%) in the group without cerclage. The five deaths occurred at a mean gestational age of 24.40 +/- 4.0 weeks and a mean birth weight of 614.00 +/- 441.73 gm. Patients with a hypoplastic cervix or prior reproductive loss had a better outcome with early cerclage than patients with a normal cervix followed expectantly. We presently lack a reliable method to detect the diethylstilbestrol-exposed patient at greatest risk for perinatal loss. Based on our experience we believe that placement of a cerclage early in pregnancy should be a strong consideration.     

Placental abruption: critical analysis of risk factors and perinatal outcomes

Objective.?To investigate risk factors and pregnancy outcome of patients with placental abruption.

Methods.?A population-based study comparing all pregnancies of women with and without placental abruption was conducted. Stratified analysis using multiple logistic regression models was performed to control for confounders.

Results.?During the study period there were 185,476 deliveries, of which 0.7% (1365) occurred in patients with placental abruption. The incidence of placental abruption increased between the years 1998 to 2006 from 0.6 to 0.8%. Placental abruption was more common at earlier gestational age. The following conditions were significantly associated with placental abruption, using a multivariable analysis with backward elimination: hypertensive disorders, prior cesarean section, maternal age, and gestational age. Placental abruption was significantly associated with adverse perinatal outcomes such as Apgar scores?<7 at 1 and 5?min and perinatal mortality. Patients with placental abruption were more likely to have cesarean deliveries, as well as cesarean hysterectomy.Using another multivariate analysis, with perinatal mortality as the outcome variable, controlling for gestational age, hypertensive disorders, etc., placental abruption was noted as an independent risk factor for perinatal mortality.

Conclusions.?Placental abruption is an independent risk factor for perinatal mortality. Since the incidence of placental abruption has increased during the last decade, risk factors should be carefully evaluated in an attempt to improve surveillance and outcome.     

The management of acardiac twins: a conservative approach

OBJECTIVE: Optimal management of acardiac twin pregnancies is controversial. Data suggest a 50% mortality rate in the "pump" twin when the pregnancy is managed expectantly. Because of increased antenatal diagnosis, outcomes in expectantly managed cases may be better than reported. Our objective was to determine the outcome of expectantly managed acardiac twin pregnancies. STUDY DESIGN: All cases of antenatally diagnosed acardiac twins delivered in our community between 1994 and 2001 were ascertained. All were managed expectantly. Perinatal outcome of pump twins was the primary outcome variable. RESULTS: Ten cases were identified. Nine women were delivered of healthy pump twins. There was one neonatal death. The mean gestational age at delivery was 34.2 weeks. The mean weights of the pump and acardiac twins were 2279 g and 1372 g, respectively. CONCLUSION: Neonatal mortality of pump twins in antenatally diagnosed acardiac twin pregnancies may be considerably less than reported. Expectant management with close antepartum surveillance deserves consideration.     

The effect on the likelihood of further pregnancy of placental abruption and the rate of its recurrence

Objective To assess the effect of having a placental abruption on 1. the probability of having further pregnancies, and 2. the rate of recurrence in such pregnancies.
Design A cohort study based on the Medical Birth Registry of Norway.
Results From 1967 to 1989, placental abruption occurred in 218/4951 subsequent deliveries after a placental abruption index case. After placental abruption with perinatal survival in the first delivery 59% of women had a further delivery, compared with 71% who did not have placental abruption at delivery. After a perinatal loss corresponding rates were 83% and 85%, respectively. Odds ratios of recurrence of abruption, crude and adjusted for maternal age, birth order and time period were 7.1 and 6.4, respectively. No secular trends were found. Caesarean section rates increased and were higher in pregnancies with recurrent placental abruption and in subsequent pregnancies without placental abruption than in the total birth population.
Conclusions Women who have placental abruption are less likely than other women to have another pregnancy. For women who do have subsequent pregnancies placental abruption occurs significantly more frequently.     

彩色超声对胎盘早剥的诊断及临床价值

目的:评价彩色多普勒超声(CDFI)及彩色多普勒能量超声(CDE)对胎盘早剥的诊断价值及临床意义。方法:回顾分析2000年1月至2003年12月本院收治的71例胎盘早剥声像特征及母儿结局。结果:彩色超声诊断胎盘早剥63例,符合率89%,漏误诊8例(占11%),71例胎盘早剥孕妇剖宫产63例,阴道分娩8例。活婴59例,其中早产儿家属放弃治疗1例,死胎12例伴子宫卒中3例。结论:CDE及CDFI对胎盘早剥的诊断准确率较高,能减少母儿并发症,降低围生儿死亡率,可作为胎盘早剥的首选检查方法。     

Incidence,obstetric risk factors and pregnancy outcome of preterm placental abruption: a retrospective analysis

Objective: To determine obstetric risk factors for the occurrence of preterm placental abruption and to investigate its subsequent perinatal outcome. Study design: A retrospective comparison of all singleton preterm deliveries complicated with placental abruption, between the years 1990-1998, to all singleton preterm deliveries without placental abruption, in the Soroka University Medical Center. Results: Placental abruption complicated 300 (5.1%) of all preterm deliveries (n = 5934). A back-step multivariable analysis found the following factors to be independently correlated with the occurrence of preterm placental abruption: grandmultiparity (more than five deliveries), early gestational age, severe pregnancy-induced hypertension, previous second-trimester bleeding and non-vertex presentation. These pregnancies had a significantly lower rate of preterm premature rupture of membranes than preterm pregnancies without placental abruption. Pregnancies complicated with preterm placental abruption had significantly higher rates of cord prolapse, non-reassuring fetal heart rate patterns, congenital malformations, Cesarean deliveries, perinatal mortality, Apgar scores lower than 7 at 5 min, postpartum anemia and delayed discharge from the hospital than did preterm deliveries without placental abruption. In order to assess whether the increased risk for perinatal mortality was due to the placental abruption, or due to its significant association with other risk factors, a multivariable analysis was constructed with perinatal mortality as the outcome variable. Placental abruption (OR 3.0, 95% CI 2.1-4.1) as well as cord prolapse, previous perinatal death, low birth weight and congenital malformations were found to be independent risk factors for perinatal mortality. Conclusion: Preterm placental abruption is an unpredictable severe complication associated with significant perinatal morbidity and mortality. Factors found to be independently associated with placental abruption were grandmultiparity, severe pregnancy-induced hypertension, malpresentation, earlier gestational age and a history of second-trimester vaginal bleeding.     

Maternal and perinatal outcome of pregnancies after the age of 45

OBJECTIVE: To describe the maternal and perinatal outcome of pregnancies in women aged 45 years or more at the time of delivery and to compare them with pregnancies in women aged between 20 and 29 years. METHODS: A retrospective review of hospital deliveries after 28 weeks gestation was performed at the Princess Badeea Teaching Hospital in North Jordan for patients delivered between 1st April 1994 and 31st December 1997. We compared the maternal and perinatal outcome of pregnancies in women aged of 45 years or more (study group, n = 114) with women aged between 20-29 years (control group, n = 121) delivered at the same hospital during the same period. RESULTS: The incidence of pregnant women aged 45 years or more was 3.3 per 1,000 births. The median maternal age was 45 years. The majority of women (81.6%) were 45 to 46 years old. Gravidity and parity was significantly higher in the study group (p < 0.0001), also antenatal and medical complications as pre-eclampsia and diabetes mellitus were higher in the study group. Caesarean section rate, incidences of placental abruption and placenta previa were more common in older patients compared with young patients (32.4 vs 10.7%, 6.1 vs 0.8% and 4.4 vs 1.6%, respectively). There were no differences in the incidences of neonatal deaths, lethal malformations and fetal weight between the 2 groups. CONCLUSION: Women aged 45 years or more at delivery may expect a good pregnancy outcome but should expect a higher incidences of placental abruption, placenta previa, preeclampsia and caesarean delivery.     

Obstetrics and perinatal outcome of pregnancies after the age of 45.

We set out to describe the maternal and perinatal outcome of pregnancies in women >/= 45 years old at the time of delivery. A retrospective review of hospital deliveries after 28 weeks of pregnancy was performed at the Princess Badeea Teaching Hospital (PBTH) in North Jordan for patients delivered between 1 April 1994 and 31 December 1997. During the study period, there were 114 women aged >/= 45 years at delivery at the PBTH. The incidence was 3.3 per 1000 births. The median maternal age was 45 years. The majority of women (81.6%) were 45-46 years old. Maternal ages were 45 (n =64), 46 (n =29), 47 (n =9), 48 (n =8), 49 (n =2) and 50 (n =2) years. Median gravidity was 10, median parity was seven. Forty-four (38.6%) patients had obstetric complications. The most frequent complication was diabetes mellitus (9.6%), followed by hypertension (4.4%). Caesarean section was performed in 32.5%. There were nine stillbirths and four early neonatal deaths, the perinatal mortality rate was 114/1000 births. We conclude that women >/= 45 years old at delivery have high perinatal mortality rate and we also noted a higher incidence of placental abruption, placenta praevia and caesarean delivery, compared with a younger group of women.     

Which types of perinatal events are predictable? A look at a risk score model

This study describes the association of a risk factor model for complicated delivery, perinatal morbidity and perinatal mortality with each of various types of delivery complications, types of perinatal morbidity and causes of perinatal mortality. The material comprises a total cohort, 4,066 pregnant women with singletons in a Danish county, and their newborn infants, of whom 494 (12%) had clinical morbidity during the first 5 days of life; 28 (0.7%) died perinatally. A set of 20 risk factors, identifiable before pregnancy, at any time during the pregnancy or at term, was devised by joining existing models for prediction of complicated delivery and of perinatal morbidity and mortality. Metabolic and disproportion-related events were well predicted by the model, inertia-related ones less so, and placental conditions not at all, except for abruption. All types of neonatal morbidity (except sepsis) were well predicted, as were deaths. The strongest predictors of perinatal death were signs of hydramnios (RR = 16.1) and growth retardation (RR = 7.2). The 20 risk factors affected 43% of the population, predicting 57% of the unfavorable perinatal events.     

Placental abruption,offspring sex,and birth outcomes in a large cohort of mothers

Objective.?To investigate stillbirth, neonatal, and perinatal death outcomes in pregnancies complicated by placental abruption, according to fetal sex.

Methods.?We utilized maternally linked cohort data files of singleton live births to mothers diagnosed with placental abruption during the period 1989 through 2005 (n?=?10,014). Logistic regression models were employed to generate adjusted odd ratios and their 95% confidence intervals. Male babies served as the referent category.

Results.?The sex ratio at birth was 1.18. The overall prevalence of stillbirth, neonatal mortality, and perinatal mortality was 7.2%, 4.5%, and 11.8%, respectively. Placental abruption was less likely to occur in mothers carrying female pregnancies than mothers of male infants (adjusted odds ratio [95% confidence interval]?=?0.89 [0.86–0.93]). There were no significant sex differences with regards to stillbirth, neonatal mortality, and perinatal mortality. Similar findings were observed for preterm and term infants.

Conclusions.?Although a preponderance of male infants was discernable among mothers with placental abruption, no sex difference in fetal survival was observed among the offspring of the mothers affected by placental abruption.     

Outcomes with premature rupture of membranes at 32 or 33 weeks when management is based on evaluation of fetal lung maturity.

OBJECTIVE: To assess outcomes of patients with premature rupture of membranes (PROM) at 32 or 33 weeks gestation. METHODS: This historical cohort study included all immune competent patients managed at our institution from October 1, 1999 to March 31, 2003 with singleton gestations and PROM at 32 or 33 weeks, and without clinical chorioamnionitis at presentation or antenatal diagnosis of a fetal anomaly. If amniotic fluid studies revealed pulmonary maturity, patients were intentionally delivered. Otherwise, they were expectantly managed until intentional delivery at 34 weeks, or labor, chorioamnionitis, or non -reassuring testing led to delivery sooner. RESULTS: For the groups with mature (n = 29) and immature or unobtainable (n = 60) fluid, respectively, rates of neonatal ICU admission (83% vs. 77%; p = 0.51), respiratory distress (41% vs. 45%; p = 0.75), mechanical ventilation (10% vs. 17%; p = 0.53), and proven neonatal infection (4% vs. 2%; p = 0.60) were similar, as were rates of other neonatal and maternal complications. The mature group had shorter mean maternal hospital stays (3.6 +/- 0.6 vs. 6.4 +/- 2.9 d; p < 0.001) and latency periods (30.2 +/- 19.3 vs. 83.8 +/- 68.7 h; p < 0.001). CONCLUSION: Compared to those managed expectantly due to immature or unavailable fetal lung studies, intentional delivery of patients with PROM at 32 or 33 weeks with mature fetal lung studies did not increase neonatal morbidity in our small cohort.     

Association of caesarean delivery for first birth with placenta praevia and placental abruption in second pregnancy

Objective  To quantify the risk of placenta praevia and placental abruption in singleton, second pregnancies after a caesarean delivery of the first pregnancy.
Design  Retrospective cohort study.
Setting  Linked birth and infant mortality database of the USA between 1995 and 2000.
Population  A total of 5 146 742 singleton second pregnancies were available for the final analysis after excluding missing information.
Methods  Multiple logistic regressions were used to describe the relationship between caesarean section at first birth and placenta praevia and placental abruption in second-birth singletons.
Main outcome measures  Placenta praevia and placental abruption.
Results  Placenta praevia was recorded in 4.4 per 1000 second-birth singletons whose first births delivered by caesarean section and 2.7 per 1000 second-birth singletons whose first births delivered vaginally. About 6.8 per 1000 births were complicated with placental abruption in second-birth singletons whose first births delivered by caesarean section and 4.8 per 1000 birth in second-birth singletons whose first births delivered vaginally. The adjusted odds ratio (95% CIs) of previous caesarean section for placenta praevia in following second pregnancies was 1.47 (1.41, 1.52) after controlling for maternal age, race, education, marital status, maternal drinking and smoking during pregnancy, adequacy of prenatal care, and fetal gender. The corresponding figure for placental abruption was 1.40 (1.36, 1.45).
Conclusion  Caesarean section for first live birth is associated with a 47% increased risk of placenta praevia and 40% increased risk of placental abruption in second pregnancy with a singleton.     

Early onset severe pre-eclampsia: expectant management at a secondary hospital in close association with a tertiary institution

Objectives   Early onset severe pre-eclampsia is ideally managed in a tertiary setting. We investigated the possibility of safe management at secondary level, in close co-operation with the tertiary centre.
Design   Prospective case series over 39 months.
Setting   Secondary referral centre.
Population   All women ( n = 131) between 24 and 34 weeks of gestation with severe pre-eclampsia, where both mother and fetus were otherwise stable.
Methods   After admission, frequent intensive but non-invasive monitoring of mother and fetus was performed. Women were delivered on achieving 34 weeks, or if fetal distress or major maternal complications developed. Transfer to the tertiary centre was individualised.
Main outcome measures   Prolongation of gestation, maternal complications, perinatal outcome and number of tertiary referrals.
Results   Most women [ n = 116 (88.5%)] were managed entirely at the secondary hospital. Major maternal complications occurred in 44 (33.6%) cases with placental abruption (22.9%) the most common. One maternal death occurred and two women required intensive care admission. A mean of 11.6 days was gained before delivery with the mean delivery gestation being 31.8 weeks. The most frequent reason for delivery was fetal distress (55.2%). There were four intrauterine deaths. The perinatal mortality rate (≥1000 g) was 44.4/1000, and the early neonatal mortality rate (≥500 g) was 30.5/1000.
Conclusions   The maternal and perinatal outcomes are comparable to those achieved by other tertiary units. This model of expectant management of early onset, severe pre-eclampsia is encouraging but requires close co-operation between secondary and tertiary institutions. Referrals to the tertiary centre were optimised, reducing their workload and costs, and patients were managed closer to their communities.     

Expectant management of partial placental abruption in previable pregnancies. A report of two cases

Placental abruption is a major cause of perinatal morbidity and mortality, especially in the preterm infant. Two patients had previable pregnancies complicated by placental abruption and large extraamniotic hematomas. Precise diagnosis and follow-up with real-time ultrasound allowed expectant management until the delivery of viable infants became possible.