Placenta accreta

A comprehensive severity score for the morbidly adherent placenta: combining ultrasound and magnetic resonance imaging

BACKGROUND

Ultrasound (US) is the first-line imaging modality to assess the morbidly adherent placenta, but sensitivity and specificity are lacking.

OBJECTIVE

This investigation aims to improve diagnostic accuracy with a comprehensive score using clinical history, US, and magnetic resonance imaging (MRI).

MATERIALS AND METHODS

We conducted a retrospective cohort study of pregnant women who received both transvaginal US and MRI with suspicion for morbidly adherent placenta between 2009 and 2016. US was scored with the following metrics: (i) previa, (ii) hypervascularity, (iii) loss of retroplacental clear space and (iv) lacunae. MRI was evaluated for (i) intraparenchymal vessels, (ii) abnormally dilated vessels, (iii) fibrin deposition, (iv) placental bulge and (v) bladder dome irregularity. Bayesian analysis was used to estimate the probability of morbidly adherent placenta for a given score. Diagnostic testing parameters were calculated.

RESULTS

Among the 41 women with concerning imaging, histologically identified disease was confirmed in 16. The probability of morbidly adherent placenta increased with the score. At the highest US score, the probability of disease was 63.7%. With the highest MRI score, the probability of adherent placentation was 90.5%. Combining the US and MRI findings had a sensitivity of 56% and a specificity of 92%.

CONCLUSION

A combined scoring system using MRI and US may accurately identify patients at risk for morbidity associated with morbidly adherent placenta.

Placenta Accreta Spectrum

Placenta accreta spectrum, formerly known as morbidly adherent placenta, refers to the range of pathologic adherence of the placenta, including placenta increta, placenta percreta, and placenta accreta. The most favored hypothesis regarding the etiology of placenta accreta spectrum is that a defect of the endometrial-myometrial interface leads to a failure of normal decidualization in the area of a uterine scar, which allows abnormally deep placental anchoring villi and trophoblast infiltration. Maternal morbidity and mortality can occur because of severe and sometimes life-threatening hemorrhage, which often requires blood transfusion. Although ultrasound evaluation is important, the absence of ultrasound findings does not preclude a diagnosis of placenta accreta spectrum; thus, clinical risk factors remain equally important as predictors of placenta accreta spectrum by ultrasound findings. There are several risk factors for placenta accreta spectrum. The most common is a previous cesarean delivery, with the incidence of placenta accreta spectrum increasing with the number of prior cesarean deliveries. Antenatal diagnosis of placenta accreta spectrum is highly desirable because outcomes are optimized when delivery occurs at a level III or IV maternal care facility before the onset of labor or bleeding and with avoidance of placental disruption. The most generally accepted approach to placenta accreta spectrum is cesarean hysterectomy with the placenta left in situ after delivery of the fetus (attempts at placental removal are associated with significant risk of hemorrhage). Optimal management involves a standardized approach with a comprehensive multidisciplinary care team accustomed to management of placenta accreta spectrum. In addition, established infrastructure and strong nursing leadership accustomed to managing high-level postpartum hemorrhage should be in place, and access to a blood bank capable of employing massive transfusion protocols should help guide decisions about delivery location.

Interpregnancy interval and abnormally invasive placentation

INTRODUCTION

The presence of a previous uterine scar is a strong risk factor for developing abnormally invasive placentation (AIP). We sought to determine whether a short interpregnancy interval predisposes to AIP. We hypothesized that a short interpregnancy interval after a previous cesarean delivery increases the risk of AIP in comparison with a longer interpregnancy interval.

MATERIAL AND METHODS

We performed a retrospective cohort study of women with a histological diagnosis of AIP and a history of a previous cesarean section. Women were included in the control group if they had a previous cesarean section with a placenta underlying the previous uterine scar or an anterior previa. The time interval between pregnancy and AIP data was analyzed using the chi-square test and two-tailed Fisher's exact test.

RESULTS

There was no statistical difference in the interpregnancy interval between women who had AIP vs the control group. Gravidity and parity were found to be significantly higher in the women with AIP vs the controls.

CONCLUSIONS

These results suggest that a short interpregnancy interval may not increase the risk of developing AIP.

Retrospective analysis of 113 consecutive cases of placenta accreta spectrum from a single tertiary care center

Objective: Placenta accreta spectrum (PAS) remains a major cause of maternal morbidity. We sought to assess the characteristics and treatment outcomes of PAS managed at a tertiary care center with high volume of PAS.Study design: Electronic medical records of all patients with diagnosis of PAS from June 2010 to October 2016 were reviewed. Details of obstetric backgrounds, predelivery diagnosis, peripartum management, and outcomes were analyzed.Results: One hundred thirteen women with PAS were identified from 50,448 deliveries during the study period. Vaginal delivery, emergency, and elective cesarean section were accomplished in 41.6, 30.1, and 28.3%, respectively. There was no maternal mortality. Approximately 41.6% of women with PAS had peripartum hysterectomy. There was a fair inverse correlation between intraoperative blood loss and gestational weeks at delivery (r = -0.311; p=.001), but not gestational weeks at diagnosis (p = .249). Cases with predelivery diagnosis (n = 29) had higher intraoperative blood loss than those diagnosed postdelivery (n = 84) (p<.001). Anterior PAS (n = 58) is associated with attachment to previous uterine scar, antepartum bleeding, and intraoperative blood loss compared to posterior PAS (n = 44) (p<.05). The PAS patients with previous uterine surgery had the highest chance of peripartum hysterectomy (p<.001).Conclusions: Contradictory to previous reports, our data suggest a more severe spectrum of PAS in those with predelivery detection earlier gestational weeks at delivery. Peripartum hysterectomy was highest in anterior PAS that attached to the previous uterine scar.

Outcomes of Planned Compared With Urgent Deliveries Using a Multidisciplinary Team Approach for Morbidly Adherent Placenta

OBJECTIVE

To compare outcomes between planned and urgent cesarean hysterectomy for morbidly adherent placenta managed by a multidisciplinary team.

METHODS

This is a retrospective case-control study of women with singleton pregnancies with antenatally suspected and pathologically confirmed morbidly adherent placenta who underwent cesarean hysterectomy between January 1, 2011, and February 30, 2017. Timing of delivery was classified as either planned (delivery at 34-35 weeks of gestation) or urgent (need for urgent delivery as a result of uterine contractions, bleeding, or both). The primary outcome variable was composite maternal morbidity. Logistic regression analysis was used to evaluate risk factors for urgent delivery.

RESULTS

One hundred thirty patients underwent hysterectomy. Sixty (46.2%) required urgent delivery. Composite maternal morbidity was identified in 34 (56.7%) of the urgent and 26 (37.1%) of the planned deliveries (P=.03). Fewer units of red blood cells and fresh frozen plasma were transfused in the planned delivery group (red blood cells, median interquartile range 3 [0-8] versus 1 [0-4], P=.02; fresh frozen plasma, median interquartile range 1 [0-2] versus 0 [0-0], P=.001). Rates of low Apgar score and respiratory distress syndrome were higher in the urgent compared with the planned delivery group (5-minute Apgar score less than 7, 34 [59.6%] versus 14 [23.3%], P<.01; respiratory distress syndrome, 34 [61.8%] versus 16 [27.1%], P<.01). A history of two or more prior cesarean deliveries was an independent predictor of urgent delivery (adjusted odds ratio 11.4, 95% CI 1.8-71.1).

CONCLUSION

Women with morbidly adherent placenta requiring urgent delivery have a worse outcome than women with planned delivery. Women with morbidly adherent placenta and two or more prior cesarean deliveries are at increased risk for urgent delivery. In such women, scheduling delivery before the standard 34- to 35-week timeframe may be reasonable.

Creating a Multidisciplinary Placenta Accreta Program

OBJECTIVE

To develop a formalized comprehensive placenta accreta (PA) program to improve maternal and neonatal outcomes associated with a PA birth.

DESIGN

To develop a clinically innovative PA program, goals were identified and teams were created to collaboratively address best practices in each phase of clinical patient care, along with the financial and marketing aspects necessary for a sustainable program.

SETTING/LOCAL PROBLEM

A Level 3 perinatal center in the Southwestern United States.

IMPLEMENTATION

A diverse multidisciplinary team addressed each aspect of care associated with a PA birth, including team members from the main operating room; trauma surgery; blood bank; interventional radiology unit; NICU; and gynecology-oncology, anesthesia, and urology departments.

MEASUREMENTS

Pre- and postprogram clinical outcome measures were examined including estimated blood loss at birth, postbirth ICU transfers and length of stay, and postpartum length of stay.

RESULTS

Clinical outcomes after program implementation showed decreased blood loss at birth (from an estimated 6,350 ml to 1,300-1,400 ml), reduced postbirth ICU length of stay (from approximately 3 days to less than 1 day, with many women bypassing ICU transfer altogether), and shortened postpartum length of stay (from 8 days to 4 days).

CONCLUSION

With implementation of this PA program, women receive a proactive approach to care that includes education, holistic care, and an organized team approach to birth made possible by the innovative care delivery model, structures, and processes. Standardized checklists and workflows help each clinician understand his or her role in the process, and resources are directed effectively and efficiently. Multidisciplinary, multispecialty collaboration results in decreased variation in care with associated improved patient outcomes.

Antenatal Management of Placenta Accreta

Predelivery diagnosis of placenta accreta, increta, and percreta (from here referred to as placenta accreta, unless otherwise noted) has increasingly created opportunities to optimize antenatal management. Despite the increased frequency of placenta accreta today, occurring in as many as 1 in 533 to 1 in 272 deliveries, high-quality data are lacking for many aspects of antenatal management. This chapter will discuss antenatal management of, and risks faced by, women with suspected placenta accreta, a condition that most frequently requires a potentially morbid cesarean hysterectomy.

Effect of Primary Elective Cesarean Delivery on Placenta Accreta: A Case-Control Study

Background

Cesarean section (CS) is an independent risk factor for placenta accreta. Some researchers think that the timing of primary cesarean delivery is associated with placenta accreta in subsequent pregnancies. The aim of this study was to investigate the risk of placenta accreta following primary CS without labor, also called primary elective CS, in a pregnancy complicated with placenta previa.

Methods:

A retrospective, single-center, case-control study was conducted at Peking University Third Hospital. Relevant clinical data of singleton pregnancies between January 2010 and September 2017 were recorded. The case group included women with placenta accreta who had placenta previa and one previous CS. Control group included women with one previous CS that was complicated with placenta previa. Maternal age, body mass index, gestational age, fetal birth weight, gravity, parity, induced abortion, the rate of women received assisted reproductive technology, other uterine surgery, and primary elective CS were analyzed between the two groups.

Results:

The rate of primary elective CS (90.1% vs. 69.9%, P < 0.001) was higher, and maternal age was younger (32.7 ± 4.7 years vs. 34.6 ± 4.0 years, P < 0.001) in case group, compared with control group. Case group also had higher gravity and induced abortions compared with the control group (both P < 0.05). Primary CS without labor was associated with significantly increased risk of placenta accreta in a subsequent pregnancy complicated with placenta previa (odds ratio: 3.32; 95% confidential interval: 1.68-6.58).

Conclusion:

Women with a primary elective CS without labor have a higher chance of developing an accreta in a subsequent pregnancy that is complicated with placenta previa.

Influence of prenatal diagnosis of abnormally invasive placenta on maternal outcome: systematic review and meta-analysis

OBJECTIVE

To ascertain the impact of prenatal diagnosis on surgical outcome of women affected by abnormally invasive placenta (AIP).

METHODS

MEDLINE, EMBASE, CINAHL and Cochrane databases were searched. Observed outcomes included: gestational age at birth (weeks), amount of blood loss (L), units of red blood cells (RBC), platelets (PLT) and fresh frozen plasma (FFP) transfused, length of stay in hospital and the intensive care unit (ICU) (days), urinary tract injury and infection. Only studies reporting the occurrence of any of the explored outcomes in women with a prenatal compared with an intrapartum diagnosis of AIP were considered eligible for inclusion. Random-effect head-to-head meta-analyses were used to analyze the data.

RESULTS

Thirteen studies were included. Women with a prenatal diagnosis of AIP had less blood loss during surgery (mean difference (MD), -0.87; 95% CI, -1.5 to -0.23), had fewer units of RBC (MD, -1.45; 95% CI, -2.9 to -0.04) and FFP (MD, -1.73; 95% CI, -3.3 to -0.2) transfused, and delivered earlier (MD, 1.33 weeks; 95% CI, -2.23 to -0.43) compared with those with an intrapartum diagnosis. The risk of admission to an ICU and length of in-hospital and in-ICU stay were not different between the groups. Prenatal diagnosis of AIP was associated with a higher risk of urinary-tract injury (odds ratio, 2.5; 95% CI, 1.3-4.6), mainly due to the higher prevalence of placenta percreta in the group with AIP diagnosed prenatally.

CONCLUSION

Prenatal diagnosis of AIP is associated with reduced hemorrhagic morbidity compared with cases in which such anomalies are detected at delivery. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Conservative management of placental invasion anomalies with an intracavitary suture technique

OBJECTIVE

To assess the efficacy and safety of a new surgical suture technique for uterine preservation among patients with placental invasion anomalies.

METHODS

The present prospective case series included women diagnosed with placental invasion anomalies undergoing cesarean deliveries who desired future fertility at the obstetrics department of a Turkish university hospital between January 10, 2013, and April 20, 2017. Patients were diagnosed with ultrasonography and Doppler ultrasonography; the type of placental invasion anomaly (placenta accreta, increta, or percreta) was confirmed intraoperatively. Surgical management involved an intracavitary suture technique after the proximal branch of the uterine artery was clamped and utero-ovarian anastomoses had been blocked. Outcomes included units of blood transfused, intraoperative and postoperative adverse events, duration of hospital admission, and hysterectomy rate.

RESULTS

There were 62 patients included. The mean operative blood loss was 1350 ± 750 mL (range 600-5000 mL). Blood transfusion required a mean of four units (range 2-15). Bleeding was controlled with the intracavitary sutures in 58 (94%) patients. Three patients experienced postoperative wound infections and two patients developed endometritis that required therapy with broad-spectrum antibiotics. The mean length of hospital stay was 3.6 ± 1.6 days (range 2-11). None of the patients required reoperation after the initial surgery.

CONCLUSION

The novel uterus-sparing suture technique was highly effective among patients with placental invasion anomalies.

Association between hypertensive disorders complicating pregnancy and risk of placenta accreta: a meta-analysis and systematic review

OBJECTIVE

Previous studies have reported a positive association between hypertensive disorders complicating pregnancy and placenta accreta. However, whether hypertensive disorders complicating pregnancy associated with placenta accreta is still not clear. The objective was to systematically review the literature to determine a possible association between hypertensive disorders complicating pregnancy and placenta accreta.

METHODS

A systematic search of PubMed database, the Cochrane Library, Willy Online Library, and ScienceDirect database through 1st December 2015, was conducted. Two authors independently assessed data extraction and quality of the studies using the Newcastle-Ottawa Scale. Assessment of heterogeneity and analysis of data were operated by Review Manager 5.3.0.

RESULTS

Three studies involving 4174 patients who developed hypertensive disorders complicating pregnancy of a total of 38,004 pregnant women were selected. The result of our meta-analysis revealed that pregnancy induced hypertension was significantly associated with a reduction of placenta accreta (OR = 0.50, 95% CI: 0.30-0.82; heterogeneity: I2 = 13%, p = 0.32).

CONCLUSIONS

Our meta-analysis demonstrated that the risk of placenta accreta is reduced in women with hypertensive disorders complicating pregnancy. Further well-designed studies are warranted to testify the result and explored any potential mechanism association between hypertensive disorders complicating pregnancy and placenta accreta.

Placenta percreta is associated with more frequent severe maternal morbidity than placenta accreta

BACKGROUND

Abnormally invasive placentation is the leading cause of obstetric hysterectomy and can cause poor to disastrous maternal outcomes. Most previous studies of peripartum management and maternal morbidity have included variable proportions of severe and less severe cases.

OBJECTIVE

The aim of this study was to compare maternal morbidity from placenta percreta and accreta.

STUDY DESIGN

This retrospective study at a referral center in Paris includes all women with abnormally invasive placentation from 2003 through 2017. Placenta percreta and accreta were diagnosed histologically or clinically. When placenta percreta was suspected before birth, a conservative approach leaving the placenta in situ was proposed because of the intraoperative risk of cesarean delivery. When placenta accreta was suspected, parents were offered a choice of a conservative approach or an attempt to remove the placenta, to be followed in case of failure by hysterectomy. Maternal outcomes were compared between women with placenta percreta and those with placenta accreta/increta. The primary outcome measure was a composite criterion of severe acute maternal morbidity including at least 1 of the following: hysterectomy during cesarean delivery, delayed hysterectomy, transfusion of ≥10 U of packed red blood cells, septic shock, acute kidney injury, cardiovascular failure, maternal transfer to intensive care, or death.

RESULTS

Of the 156 women included, 51 had placenta percreta and 105 placenta accreta. Abnormally invasive placentation was suspected antenatally nearly 4 times more frequently in the percreta than the accreta group (96.1% [49/51] vs 25.7% [27/105], P < .01). Among the 76 women with antenatally suspected abnormally invasive placentation (48.7%), the rate of antenatal decisions for conservative management was higher in the percreta than the accreta group (100% [49/49] vs 40.7% [11/27], P < .01). The composite maternal morbidity rate was significantly higher in the percreta than the accreta group (86.3% [44/51] vs 28/105 [26.7%], P < .001). A secondary analysis restricted to women with an abnormally invasive placentation diameter >6 cm showed similar results (86.0% [43/50) vs 48.7% [19/38), P < .01). The rate of hysterectomy during cesareans was significantly higher in the percreta than the accreta group (52.9% [27/51] vs 20.9% [22/105], P < .01) as was the total hysterectomy rate (43/51 [84.3%] vs 23.8% [25/105], P < .01).

CONCLUSION

Severe maternal morbidity is much more frequent in women with placenta percreta than with placenta accreta, despite multidisciplinary planning, management in a referral center, and better antenatal suspicion.

Diagnostic accuracy of ultrasound in detecting the depth of invasion in women at risk of abnormally invasive placenta: A prospective longitudinal study

INTRODUCTION

The aim of this study was to assess the diagnostic accuracy of ultrasound in detecting the depth of abnormally invasive placenta in women at risk.

MATERIAL AND METHODS

Prospective longitudinal study including women with placenta previa and at least one prior cesarean delivery or uterine surgery. Depth of abnormally invasive placenta was defined as the degree of trophoblastic invasion through the myometrium and was assessed with histopathological analysis. The ultrasound signs explored were: loss of clear zone, placental lacunae, bladder wall interruption, uterovesical hypervascularity, and increased vascularity in the parametrial region.

RESULTS

In all, 210 women were included in the analysis. When using at least one sign, ultrasound had an overall sensitivity of 100% (95% CI 96.5-100) and overall specificity of 61.9 (95% CI 51.9-71.2) for all types of abnormally invasive placenta. Using two ultrasound signs increased the diagnostic accuracy in terms of specificity (100%, 95% CI 96.5-100) but did not affect sensitivity. When stratifying the analysis according to the depth of placental invasion, using at least one sign had a sensitivity of 100% (95% CI 93.7-100) and 100% (95% CI 92.6-100) for placenta accreta/increta and percreta, respectively. Using three ultrasound signs improved the detection rate for placenta percreta with a sensitivity of 100% (95% CI 92.6-100) and a specificity of 77.2% (95% CI 69.9-83.4).

CONCLUSION

Ultrasound has a high diagnostic accuracy in detecting the depth of placental invasion when applied to a population with specific risk factors for anomalies such as placenta previa and prior cesarean delivery or uterine surgery.

Delayed surgical and non-surgical treatment of placental remnants: no difference was found in the clinical efficacy and long-term pregnancy outcomes

Purpose

In a tertiary hospital, patients facing delayed treatment with placental remnants were common. The aim of this study was to assess the clinical efficacy and long-term pregnancy outcomes of the delayed surgical/non-surgical treatment for placental remnants.

Patients and methods

The records of referral patients with placental remnants after second/third-trimester delivery/termination of pregnancy were retrospectively analyzed. A long-term follow-up was made by phone to inquire about the future pregnancy outcomes. The measurements of clinical efficacy included the postpartum intervals for Doppler ultrasound to become normal and for menstrual cycle to return to normal. Conception rate, interval for future pregnancy and obstetric outcomes were used to assess future pregnancies.

Results

A total of 65 patients, who were clinically diagnosed with placental remnants after termination of pregnancy at the second or third trimester from 2000 to 2016, were included in this study. Delayed surgical treatments employed at a median interval (MI) of 2.7 months after termination of pregnancy had a similar interval for ultrasound (P=0.353) and menstrual cycle (P=0.751) to return to normal compared with non-surgical treatments. For non-lactating patients who accepted expectant treatments, the postpartum interval for ultrasound to return to normal was significantly longer than that for menstrual cycle to become normal (MI=3.6, 1.5 months, respectively, P=0.000). For all of the patients successfully treated, the conception rate (P=1.00), the interval for a second pregnancy (P=0.771), ongoing-pregnancy/live birth rate (P=0.419) and the recurrence rate of placenta accrete (P=1.00) there was no significant difference between non-surgical and surgical treatments. Assisted selective uterine artery embolization at an MI of 23 days after the termination of pregnancy had a longer interval for ultrasound to become normal than single expectant treatment (P=0.017). For all patients after expectant treatments, 94.1% of patients conceived after an MI of 12.5 months with the ongoing-pregnancy/live birth rate of 66.7% and a 33.3% recurrence rate of placenta accreta.

Conclusion

According to our experience, delayed surgeries at a postpartum interval of 2.7 months might have similar clinical efficacy and long-term pregnancy outcomes with expectant treatment in treating placental remnants.

Management strategies for patients with placenta accreta spectrum disorders who underwent pregnancy termination in the second trimester: a retrospective study

Background

The unique clinical features of pregnancy termination in the second trimester with concurrent placenta accreta spectrum (PAS) disorders place obstetricians in a complex and delicate situation. However, there are limited data on this rare and dangerous condition. The objective of this research was to investigate and evaluate the clinical management strategies of this patient group.

Methods

The medical records of patients who were diagnosed and treated in our hospital from December 2005 and December 2015 were retrospectively reviewed.

Results

A total of 29 patients were included in this analysis. A prenatal diagnosis was suspected in 8 (27.6%) patients, and the remaining 21 (72.4%) patients were diagnosed after pregnancy termination in the second trimester. In the subgroup with a prenatal diagnosis, a planned hysterotomy was performed in 7 patients who had total placenta previa and previous cesarean delivery. The remaining patient received medical termination. A subtotal hysterectomy was performed in 3 (10.3%) patients for life-threatening bleeding during hysterotomy, and the uterus was preserved with an in situ placenta in the remaining 5 patients. In the subgroup with a postnatal diagnosis, the implanted placenta remained partly or completely in situ in all 21 patients under informed consent. Ultimately, the implanted placenta remained partly or completely in situ in 26 (89.7%) patients in the two subgroups. With the application of adjuvant treatments, including uterine artery embolization and medication followed by curettage under ultrasound guidance, the implanted placenta was passed 76.6 (range: 19 to 192) days after termination. Uterus preservation was achieved in all 26 patients. The complications associated with conservative management included delayed postnatal hemorrhaging (2 cases, 7.7%), fever (6 cases, 23.1%), G1 transaminase disorder (4 cases, 15.4%), and myelosuppression (1 case, 3.8%). Seven women (26.9%) had a spontaneous pregnancy after conservative management, and no patient experienced recurrent PAS disorders.

Conclusions

Leaving the implanted placenta in situ is the preferred choice for patients with PAS disorders who underwent pregnancy termination in the second trimester and desired fertility preservation. Multiple adjuvant treatment modalities, either alone or in combination, may help to promote the passing or absorption of the implanted placenta under close monitoring.

Platelet Counts during Pregnancy

BACKGROUND

Platelet counts of less than 150,000 per cubic millimeter during uncomplicated pregnancies are described as gestational thrombocytopenia if no alternative cause is identified. Platelet counts may be even lower in women with pregnancy-related complications. However, the occurrence and severity of thrombocytopenia throughout pregnancy are not defined.

METHODS

We evaluated platelet counts throughout pregnancy in women who delivered at Oklahoma University Medical Center between 2011 and 2014. These platelet counts were compared with those of nonpregnant women who were included in the National Health and Nutrition Examination Survey from 1999 through 2012.

RESULTS

Among the 15,723 deliveries that occurred during the study period, 7351 women had sufficient data for our analyses. Of these women, 4568 had uncomplicated pregnancies, 2586 had pregnancy-related complications, and 197 had preexisting disorders associated with thrombocytopenia. Among the women who had uncomplicated pregnancies, the mean platelet count in the first trimester (mean gestation, 8.7 weeks) was 251,000 per cubic millimeter, which was lower than the mean platelet count in the 8885 nonpregnant women (273,000 per cubic millimeter) (P<0.001). At the time of delivery, 9.9% of the women with uncomplicated pregnancies had a platelet count below 150,000 per cubic millimeter. During the course of the uncomplicated pregnancies and deliveries, only 45 women (1.0%) had a platelet count below 100,000 per cubic millimeter. Among the 12 women with uncomplicated pregnancies who had a platelet count below 80,000 per cubic millimeter, only 5 (0.1%, among whom the range of platelet counts was 62,000 to 78,000 per cubic millimeter; median, 65,000) were identified by medical record review as having no alternative cause for the thrombocytopenia. Platelet counts of less than 150,000 per cubic millimeter at the time of delivery were more common among women who had pregnancy-related complications than among women who had uncomplicated pregnancies (11.9% vs. 9.9%, P=0.01). Throughout their pregnancies and deliveries, 59 women (2.3%) with pregnancy-related complications had a platelet count below 100,000 per cubic millimeter, and 31 (1.2%) had a platelet count below 80,000 per cubic millimeter.

CONCLUSIONS

Mean platelet counts decreased during pregnancy in all the women, beginning in the first trimester. In women who have a platelet count of less than 100,000 per cubic millimeter, a cause other than pregnancy or its complications should be considered. (Funded by the National Heart, Lung, and Blood Institute.).

Magnetic resonance imaging is often misleading when used as an adjunct to ultrasound in the management of placenta accreta spectrum disorders

BACKGROUND

Magnetic resonance imaging is reported to have good sensitivity and specificity in the diagnosis of placenta accreta spectrum disorders, and is often used as an adjunct to ultrasound. But the additional utility of obtaining magnetic resonance imaging to assist in the clinical management of patients with placenta accreta spectrum disorders, above and beyond the information provided by ultrasound, is unknown.

OBJECTIVE

We aimed to determine whether magnetic resonance imaging provides data that may inform clinical management by changing the sonographic diagnosis of placenta accreta spectrum disorders.

STUDY DESIGN

In all, 78 patients with sonographic evidence or clinical suspicion of placenta accreta spectrum underwent magnetic resonance imaging of the abdomen and pelvis in orthogonal planes through the uterus utilizing T1- and T2-weighted imaging sequences at the University of Utah and the University of Colorado from 1997 through 2017. The magnetic resonance imaging was interpreted by radiologists with expertise in diagnosis of placenta accreta spectrum who had knowledge of the sonographic interpretation and clinical risk factors for placenta accreta spectrum disorders. The primary outcome was a change in diagnosis from sonographic interpretation that could alter clinical management, which was defined a priori. Diagnostic accuracy was verified by surgical and histopathologic diagnosis at the time of delivery.

RESULTS

A change in diagnosis that could potentially alter clinical management occurred in 28 (36%) cases. Magnetic resonance imaging correctly changed the diagnosis in 15 (19%), and correctly confirmed the diagnosis in 34 (44%), but resulted in an incorrect change in diagnosis in 13 (17%), and an incorrect confirmation of ultrasound diagnosis in 15 (21%). Magnetic resonance imaging was not more likely to change a diagnosis in the 24 cases of posterior and lateral placental location compared to anterior location (33% vs 37%, P = .84). Magnetic resonance imaging resulted in overdiagnosis in 23% and in underdiagnosis in 14% of all cases. When ultrasound suspected severe disease (percreta) in 14 cases, magnetic resonance imaging changed the diagnosis in only 2 cases. Lastly, the proportion of accurate diagnosis with magnetic resonance imaging did not improve over time (61-65%, P = .96 for trend) despite increasing volume and increasing numbers of changed diagnoses.

CONCLUSION

Magnetic resonance imaging resulted in a change in diagnosis that could alter clinical management of placenta accreta spectrum disorders in more than one third of cases, but when changed, the diagnosis was often incorrect. Given its high cost and limited clinical value, magnetic resonance imaging should not be used routinely as an adjunct to ultrasound in the diagnosis of placenta accreta spectrum until evidence for utility is clearly demonstrated by more definitive prospective studies.

Clinical application of stage operation in patients with placenta accreta after previous caesarean section

To explore the clinical value of stage operation to patients with placenta accreta after previous caesarean section (CS).Nineteen women with medium and late pregnancies diagnosed with placenta accreta after previous CS were enrolled in this retrospective study and all underwent stage operation. Postpartum hemorrhage volume, red blood cells (RBC) transfusion, uterus retention rate, postpartum complications, and menstrual recovery were analyzed to evaluate the value of stage operation in patients with placenta accreta.Four of 19 cases were performed uterus curettage after 63, 38, 56, and 52 days of CS. Total hysterectomy was performed in 2 cases after 44 and 57 days of first-stage CS. Thirteen cases had placenta well discharged after treatment with the traditional Chinese medicine (TCM) Shenghua Decoction. The uterus retention rate was 89.48% (17/19). Mean postpartum hemorrhage volume was 1594.74 ± 1134.06 (400-4500) mL, mean volume of total hemorrhage was 1878.42 ± 1276.96 (400-4500) mL, mean RBC transfusion was 868.42 ± 816.53 (0.00-2400.00) mL. Postpartum bleeding volume showed≤1000 mL in 8 patients and ≤500 mL in 4 patients.Stage operation reduces postpartum hemorrhage volume and cesarean hysterectomy morbidity in patients with placenta accreta. However, infection and late postpartum hemorrhage should be monitored closely.

Endovascular Interventions for the Morbidly Adherent Placenta

Morbidly adherent placentas are a spectrum of abnormalities ranging from placental invasion of the myometrium to invasion past the myometrium and muscular layers into adjacent structures. This entity is becoming more prevalent recently with increased number of cesarean deliveries. Given the high risk of morbidity and mortality, this was traditionally treated with pre-term planned cesarean hysterectomy. However, recently, uterine preservation techniques have been implemented for those women wishing to preserve future fertility or their uterus. Early identification is crucial as studies have shown better outcomes for women treated at tertiary care facilities by a dedicated multidisciplinary team. Interventional radiologists are frequently included in the care of these patients as there are several different endovascular techniques which can be implemented to decrease morbidity in these patients both in conjunction with cesarean hysterectomy and in the setting of uterine preservation. This article will review the spectrum of morbidly adherent placentas, imaging, as well as the surgical and endovascular interventions implemented in the care of these complex patients.

Diagnostic accuracy of cystoscopy and ultrasonography in the prenatal diagnosis of abnormally invasive placenta

The aim of this study was to compare the accuracy of cystoscopy and ultrasonography for the prenatal diagnosis of abnormally invasive placenta (AIP), including its subgroups: placenta accreta (PA), placenta increta (PI), and placenta percreta (PP).A retrospective observational study including a total of 85 pregnant women at high risk for AIP underwent prenatal cystoscopy and ultrasonography evaluations. The sensitivity (Se), specificity (Sp), positive predictive value, negative predictive value, and exact diagnosed were calculated and compared for both cystoscopy and ultrasonography. Se and Sp values of cystoscopy and ultrasonography were compared by means of the McNemar test.Of the 85 patients, there were 24 (28.2%) PA, 35 (41.2%) PI, 4 (4.7%) PP, and 22 (25.9%) nonadherent placenta. The mean maternal age and gestational age of delivery were 31.88 ± 4.42 years and 36.14 ± 1.84 weeks, respectively. No one was found to develop any complications with cystoscopy like urinary tract infection, or ureteral injury or perforations. Se in the diagnosis of AIP was 50.8% with ultrasonography and 61.9% for cystoscopy. Sp was 86.4% with cystoscopy and 72.7% for ultrasonography. In subgroups, Se with cystoscopy was 25.0%, 62.9%, and 100.0% in PA, PI, and PP, respectively, and 37.5%, 74.3%, and 100.0%, respectively, for ultrasonography; Sp remained unchanged with 86.4% for cystoscopy and 72.7% for ultrasonography. After McNemar test, no difference was found in either Se or Sp between cystoscopy and ultrasonography in AIP and its subgroups.According to the depth of invasion, the diagnostic value of cystoscopy and ultrasonography is all conspicuous increased and they have similar test validity for prenatal diagnosis of AIP and its subgroups.

First-trimester detection of abnormally invasive placenta in high-risk women: systematic review and meta-analysis

OBJECTIVES

The primary aim of this systematic review was to ascertain whether ultrasound signs suggestive of abnormally invasive placenta (AIP) are present in the first trimester of pregnancy. Secondary aims were to ascertain the strength of association and the predictive accuracy of such signs in detecting AIP in the first trimester.

METHODS

An electronic search of MEDLINE, EMBASE, CINAHL and Cochrane databases (2000-2016) was performed. Only studies reporting on first-trimester diagnosis of AIP that was subsequently confirmed in the third trimester either during operative delivery or by pathological examination were included. Meta-analysis of proportions, random-effects meta-analysis and hierarchical summary receiver-operating characteristics curve analysis were used to analyze the data.

RESULTS

Seven studies, involving 551 pregnancies at high risk of AIP, were included. At least one ultrasound sign suggestive of AIP was detected in 91.4% (95% CI, 85.8-95.7%) of cases with confirmed AIP. The most common ultrasound feature in the first trimester of pregnancy was low implantation of the gestational sac close to a previous uterine scar, which was observed in 82.4% (95% CI, 46.6-99.8%) of cases. Anechoic spaces within the placental mass (lacunae) were observed in 46.0% (95% CI, 10.9-83.7%) and a reduced myometrial thickness in 66.8% (95% CI, 45.2-85.2%) of cases affected by AIP. Pregnancies with a low implantation of the gestational sac had a significantly higher risk of AIP (odds ratio, 19.6 (95% CI, 6.7-57.3)), with a sensitivity and specificity of 44.4% (95% CI, 21.5-69.2%) and 93.4% (95% CI, 90.5-95.7%), respectively.

CONCLUSIONS

Ultrasound signs of AIP can be present during the first trimester of pregnancy, even before 11 weeks' gestation. Low anterior implantation of the placenta/gestational sac close to or within the scar was the most commonly seen early ultrasound sign suggestive of AIP, although its individual predictive accuracy was not high. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

The diagnosis and management of morbidly adherent placenta

The incidence of morbidly adherent placenta (MAP) has risen 13-fold since the early 1900s and is directly correlated with the rising rate of cesarean delivery. It is important for clinicians to screen all pregnancies for MAP at the time of routine second-trimester ultrasonography. In addition, patients with risk factors (e.g., multiple prior cesarean deliveries) should undergo targeted screening for MAP. Optimal maternal and fetal outcomes for these high-risk pregnancies result from accurate prenatal diagnosis and comprehensive multidisciplinary preparation and delivery between 34 and 36 weeks of gestation. There continue to be large knowledge gaps with respect to the optimal management of this condition especially around diagnosis, obstetric care, timing of delivery, and surgical management. Accordingly, most recommendations are based on expert opinion rather than on high-quality evidence. Prospective clinical trials are needed to address knowledge gaps and to continue to improve outcomes.

Placental implantation abnormalities: a modern approach

PURPOSE OF REVIEW

Placental implantation abnormalities (PIAs) comprise a large group of disorders associated with significant maternal, fetal, and neonatal morbidity.

RECENT FINDINGS

Risk factors include prior uterine surgery/myometrial scarring and the presence of placenta previa with or without prior cesarean delivery. Newly identified risk factors include previous prelabor cesarean delivery and previous postpartum hemorrhage. PIAs contribute substantially to preterm birth with prematurity rates ranging from 38 to 82%. Diagnosis is typically made by ultrasound in the second or third trimester; transvaginal ultrasound and color Doppler are useful in evaluating for placental invasion, placental edge thickness, presence of fetal vessels, and cervical length. Suggestive MRI features include increased vascularity, dark T2 bands, uterine bulging, thin or indistinct myometrium, and loss of dark T2 interface. An important first-trimester finding is the implantation of the gestational sac into prior hysterotomy scar (cesarean scar pregnancy). Recommendations for delivery are universally preterm and based on expert opinion. Proposed management strategies are outlined depending on cervical length, distance between internal cervical os and placenta, and placental edge thickness.

SUMMARY

There has been a recent shift in focus to individualizing management in order to improve delivery timing and in some cases even decrease risks associated with prematurity. There is a need for larger prospective studies or randomized trials to show that individualizing care can improve outcomes.

Society for Maternal-Fetal Medicine (SMFM) Consult Series #44: Management of bleeding in the late preterm period

Third-trimester bleeding is a common complication arising from a variety of etiologies, some of which may initially present in the late preterm period. Previous management recommendations have not been specific to this gestational age window, which carries a potentially lower threshold for delivery. The purpose of this document is to provide guidance on management of late preterm (34 0/7-36 6/7 weeks of gestation) vaginal bleeding. The following are Society for Maternal-Fetal Medicine recommendations: (1) we recommend delivery at 36-37 6/7 weeks of gestation for stable women with placenta previa without bleeding or other obstetric complications (GRADE 1B); (2) we do not recommend routine cervical length screening for women with placenta previa in the late preterm period due to a lack of data on an appropriate management strategy (GRADE 2C); (3) we recommend delivery between 34 and 37 weeks of gestation for stable women with placenta accreta (GRADE 1B); (4) we recommend delivery between 34 and 37 weeks of gestation for stable women with vasa previa (GRADE 1B); (5) we recommend that in women with active hemorrhage in the late preterm period, delivery should not be delayed for the purpose of administering antenatal corticosteroids (GRADE 1B); (6) we recommend that fetal lung maturity testing should not be used to guide management in the late preterm period when an indication for delivery is present (GRADE 1B); and (7) we recommend that antenatal corticosteroids should be administered to women who are eligible and are managed expectantly if delivery is likely within 7 days, the gestational age is between 34 0/7 and 36 6/7 weeks of gestation, and antenatal corticosteroids have not previously been administered (GRADE 1A).

Association of Placenta Previa with a History of Previous Cesarian Deliveries and Indications for a Possible Role of a Genetic Component

A prior Cesaria section (C-section) is an important risk factor that leads to endometrial damage and abnormal implantation of the placenta. Our retrospective study aims to correlate the frequency of placenta previa to previous C-sections, to determine the effect of male gender in this condition and to evaluate further the maternal outcome. Seventy-six cases with placenta previa were selected out of 5200 live births. Diagnosis was confirmed by ultrasound and in the operating theater. In the 76 women examined, we found 50 cases with a history of a previous C-section (66.0%) and 49 male offspring (65.0%) (p <0.001), with a mean birth weight of 2635 ± 740 g. Of all these patients, six (8.0%) cases developed placenta percreta, seven (9.0%) were transferred to the intensive care unit (ICU), 14 (18.0%) women needed blood transfusion and eight (11.0%) underwent hysterectomy. The results of our series show a strong correlation of placenta previa to a history of previous C-sections and a predominance of male fetuses. Early recognition and proper monitoring could minimize the possibility of a poor outcome.

Diagnostic accuracy of magnetic resonance imaging in detecting the severity of abnormal invasive placenta: a systematic review and meta-analysis

INTRODUCTION

Accurate prenatal diagnosis of abnormally invasive placenta (AIP) is fundamental because it significantly reduces maternal morbidities.

MATERIAL AND METHODS

Medline, Embase, CINAHL and the Cochrane databases were searched. The primary aim of the present review was to elucidate the diagnostic accuracy of prenatal magnetic resonance imaging (MRI) in recognizing the severity of AIP, defined as the depth and topography of invasion. The secondary aim was to ascertain the strength of association between each MRI sign and the depth of placental invasion and to test their individual predictive accuracy in detecting such invasion. Inclusion criteria were studies on women who had prenatal MRI for ultrasound suspicion or the presence of clinical risk factors for AIP. Estimates of sensitivity, specificity, positive and negative likelihood ratios and diagnostic odds ratio were calculated using the hierarchical summary receiver characteristics curve model, and individual data random-effect logistic regression was used to calculate OR.

RESULTS

Twenty studies (1080 pregnancies undergoing MRI mainly for the ultrasound suspicion of AIP) were included. MRI showed a sensitivity of 94.4% [95% confidence interval (CI) 15.8-99.9], 100% (95% CI 75.3-100) and 86.5% (95% CI 74.2-94.4) for detection of placenta accreta, increta and percreta, respectively; the corresponding values for specificity were 98.8% (95% CI 70.7-100), 97.3% (95% CI 93.3-99.3), 96.8% (95% CI 93.5-98.7). MRI identified 100% of cases with S1 and 100% of those with S2 invasion confirmed at surgery. Among the different MRI signs, intra-placental dark bands showed the best sensitivity for the detection of placenta accreta, increta and percreta; as well as abnormal intra-placental vascularity, uterine bulging was associated with a higher risk of increta and percreta, exophitic mass and bladder tenting with placenta percreta.

CONCLUSION

Prenatal MRI has an excellent diagnostic accuracy in identifying the depth and the topography of placental invasion. However, these findings come mainly from studies in which MRI was performed as a secondary imaging tool in women already screened for AIP on ultrasound and might not reflect its actual diagnostic performance in detecting the severity of these disorders.

A nationwide population-based cohort study of peripartum hysterectomy and arterial embolisation in Belgium: results from the Belgian Obstetric Surveillance System

OBJECTIVES

To assess the prevalence of major obstetric haemorrhage managed with peripartum hysterectomy and/or interventional radiology (IR) in Belgium. To describe women characteristics, the circumstances in which the interventions took place, the management of the obstetric haemorrhage, the outcome and additional morbidity of these women.

DESIGN

Nationwide population-based prospective cohort study.

SETTING

Emergency obstetric care. Participation of 97% of maternities covering 98.6% of deliveries in Belgium.

PARTICIPANTS

All women who underwent peripartum hysterectomy and/or IR procedures in Belgium between January 2012 and December 2013.

RESULTS

We obtained data on 166 women who underwent peripartum hysterectomy (n=84) and/or IR procedures (n=102), corresponding to 1 in 3030 women undergoing a peripartum hysterectomy and another 1 in 3030 women being managed by IR, thereby preserving the uterus. Seventeen women underwent hysterectomy following IR and three women needed further IR despite hysterectomy. Abnormal placentation and/or uterine atony were the reported causes of haemorrhage in 83.7%. Abnormally invasive placenta was not detected antenatally in 34% of cases. The interventions were planned in 15 women. Three women were transferred antenatally and 17 women postnatally to a hospital with emergency IR service. Urgent peripartum hysterectomy was averted in 72% of the women who were transferred, with no significant difference in need for transfusion. IR procedures were able to stop the bleeding in 87.8% of the attempts. Disseminated intravascular coagulation secondary to major haemorrhage was reported in 32 women (19%).

CONCLUSION

The prevalence in Belgium of major obstetric haemorrhage requiring peripartum hysterectomy and/or IR is estimated at 6.6 (95% CI 5.7 to 7.7) per 10 000 deliveries. Increased clinician awareness of the risk factors of abnormal placentation could further improve the management and outcome of major obstetric haemorrhage. A case-by-case in-depth analysis is necessary to reveal whether the hysterectomies and arterial embolisations performed in this study were appropriate or preventable.

Emergency obstetric hysterectomy for life-threatening postpartum hemorrhage: A 12-year review

The aim of the study was to review the operative experiences of emergency hysterectomy for life-threatening postpartum hemorrhage (PPH) performed over a 12-year period at Fujian Provincial Maternity and Children's Hospital; to examine the incidence and risk factors for emergency obstetric hysterectomy; and to evaluate the curative effectiveness and safety of subtotal hysterectomy for life-threatening PPH.The records of all cases of emergency obstetric hysterectomy performed at Fujian Maternity and Children Health Hospital between January 2004 and June 2016 were analyzed. The incidence, risk factors, and outcomes of hysterectomy, the peripartum complications, and the coagulation function indices were evaluated.A total of 152,023 of women were delivered. The incidence of emergency postpartum hysterectomy was 0.63 per 1000 deliveries: 96 patients underwent hysterectomy for uncontrolled PPH, 19 (0.207‰) underwent hysterectomy following vaginal delivery, and 77 (1.28‰) underwent the procedure following cesarean delivery (P < .001). Common risk factors included postpartum prothrombin activity ≤ 50% (61.5%), placenta accreta (43.76%), uterine atony (37.5%), uterine rupture (17.5%), and grand multiparity > 6 (32.3%). Forty-one patients underwent subtotal abdominal hysterectomy (STH) and 55 patients underwent total abdominal hysterectomy (TH). The mean operation time was significantly shorter for TH (193.59 ± 83.41 minutes) than for STH (142.86 ± 78.32 minutes; P = .002). The mean blood loss was significantly greater for TH (6832 ± 787 mL) than for STH (6329 ± 893 mL; P = .003). The mean number of red cell units transfusion was higher during TH (16.24 ± 9.48 units vs 12.43 ± 7.2, respectively; P = .047). Postoperative prothrombin activity was significantly higher than preoperative levels (56.84 ± 14.74 vs 44.39 ± 15.69, respectively; P < .001) in women who underwent TH and in those who underwent STH (57.63 ± 15.68 vs 47.87 ± 12.86, respectively; P < .001). There was no significant difference in the maternal complications after TH or STH for PPH.Cesarean deliveries were associated with an increased risk of emergency hysterectomy, and postpartum prothrombin activity < 50% was the greatest risk factor for hysterectomy in most women who underwent hysterectomy. STH was the preferred procedure for emergency obstetric hysterectomy.

Aortoiliac Thrombosis Following Tranexamic Acid Administration During Urgent Cesarean Hysterectomy: A Case Report

Postpartum hemorrhage (PPH) contributes to 25% of maternal deaths worldwide. Abnormal placentation is a well-known culprit of PPH. Although controversial, iliac artery balloon occlusion has been used in patients to decrease bleeding. The use of antifibrinolytic agents, such as tranexamic acid (TXA), have gained popularity in the management of PPH. We present a 35-year-old parturient with placenta percreta that was managed with internal iliac artery balloon occlusion with concomitant use of TXA during urgent cesarean hysterectomy with subsequent aortoiliac thrombosis formation. The role of both TXA and arterial balloons in PPH, along with their respective limitations, are discussed.

Improvement in Outcomes of Major Obstetric Hemorrhage Through Systematic Change

OBJECTIVE

To report the outcomes over 14 years of sustained systematic institutional focus on the care of women with major obstetric hemorrhage, defined as estimated blood loss greater than 1,500 mL.

METHODS

A retrospective cohort study of women with major obstetric hemorrhage at our hospital from 2000 to 2014 compares baseline conditions (age, multiparity, prior cesarean delivery, morbidly adherent placenta), morbidity (lowest mean temperature, lowest mean pH, coagulopathy, hysterectomy), and mortality among three time periods (period 1=January 2000 to December 2001, period 2=January 2002 to August 2005, period 3=September 2005 to December 2014). We also describe the systematic changes that helped to sustain our improved outcomes.

RESULTS

During the three time periods, there were 5,811, 12,912, and 38,971 births; the rate of major obstetric hemorrhage increased over these periods: 2.1, 3.8 and 5.3 cases per 1,000 births, respectively. Two deaths from hemorrhage occurred in period 1 and none thereafter. Among women who experienced massive hemorrhage, morbidity significantly improved in each successive period: median lowest pH increased from 7.23 to 7.34 to 7.35 (periods 2 and 3 significantly higher than period 1), median lowest maternal temperature (°C) improved, 35.2 to 36.1 to 36.4 (all difference significant), and the rate of coagulopathy decreased, 58.3% to 28.6% to 13.2% (period 3 significantly lower than periods 1 and 2) (all P values <.001). Peripartum hysterectomies were more frequent and more frequently planned over time rather than urgent in each successive period: 0 of 6 to 6 of 18 (33%) to 31 of 64 (48.4%) (P=.044). During period 3, we reorganized the obstetric rapid response team, instituted a massive transfusion protocol and use of uterine balloon tamponade, and promoted a culture of safety in two ways-through more intensive education regarding hemorrhage and escalation (encouraging all staff to contact senior leaders).

CONCLUSION

A sustained level of patient safety is achievable when treating major obstetric hemorrhage, as shown by a progressive decrease in morbidity despite increasing rates of hemorrhage.