Placenta accreta spectrum care infrastructure: an evidence-based review of needed resources supporting placenta accreta spectrum care.

The incidence of placenta accreta spectrum, the deeply adherent placenta with associated increased risk of maternal morbidity and mortality, has seen a significant rise in recent years. Therefore, there has been a rise in clinical and research focus on this complex diagnosis. There is international consensus that a multidisciplinary coordinated approach optimizes outcomes. The composition of the team will vary from center to center; however, central themes of complex surgical experts, specialists in prenatal diagnosis, critical care specialists, neonatology specialists, obstetrics anesthesiology specialists, blood bank specialists, and dedicated mental health experts are universal throughout. Regionalization of care is a growing trend for complex medical needs, but the location of care alone is just a starting point. The goal of this article is to provide an evidence-based framework for the crucial infrastructure needed to address the unique antepartum, delivery, and postpartum needs of the patient with placenta accreta spectrum. Rather than a clinical checklist, we describe the personnel, clinical unit characteristics, and breadth of contributing clinical roles that make up a team. Screening protocols, diagnostic imaging, surgical and potential need for critical care, and trauma-informed interaction are the basis for comprehensive care. The vision from the author group is that this publication provides a semblance of infrastructure standardization as a means to ensure proper preparation and readiness.

A Retrospective Review of Social Deprivation Index and Maternal Outcomes with Placenta Accreta Spectrum from a Single Referral Center.

OBJECTIVE: Little is known about how community characteristics influence placenta accreta spectrum (PAS) outcomes. Our objective was to evaluate whether adverse maternal outcomes among pregnant people (gravidae) with PAS delivering at a single referral center differ by community-level measures of social deprivation. STUDY DESIGN: We conducted a retrospective cohort study of singleton gravidae with histopathology confirmed PAS delivering from January 2011 to June 2021 at a referral center. Data abstraction collected relevant patient information, including resident zip code, which was linked to Social Deprivation Index (SDI) score (a measure of area-level social deprivation). SDI scores were divided into quartiles for analysis. Primary outcome was a composite of maternal adverse outcomes. Bivariate analyses and multivariable logistic regression were performed. RESULTS: Among our cohort (n = 264), those in the lowest (least deprived) SDI quartile were older, had lower body mass index, and were more likely to identify as non-Hispanic white. Composite maternal adverse outcome occurred in 81 (30.7%), and did not differ significantly by SDI quartile. Intraoperative transfusion of ≥4 red blood cell units occurred more often among those living in deprived areas (31.2% in the highest [most deprived] vs. 22.7% in the lowest [least deprived] SDI quartile, p = 0.04). No other outcomes differed by SDI quartile. In multivariable logistic regression, a quartile increase in SDI was associated with 32% increased odds of transfusion of ≥4 red blood cell units (adjusted odds ratio: 1.32, 95% confidence interval: 1.01-1.75). CONCLUSION: Within a cohort of gravidae with PAS delivered at a single referral center, we found that those living in more socially deprived communities were more likely to receive transfusion of ≥4 red blood cell units, but other maternal adverse outcomes did not differ. Our findings highlight the importance of considering how characteristics of the surrounding community can impact PAS outcomes and may assist with risk stratification and resource deployment. KEY POINTS: · Little is known about how community characteristics influence PAS outcomes.. · In a referral center, transfusion was more common in gravidae living in socially deprived areas.. · Future research should consider how community characteristics can impact PAS outcomes..

Basal Plate Myofibers and the Risk of Placenta Accreta Spectrum in the Subsequent Pregnancy: A Large Single-Center Cohort.

OBJECTIVE: We aimed to evaluate whether there is a significant association between a placental pathology diagnosis basal plate myofibers (BPMF) in an index pregnancy with placenta accreta spectrum (PAS) in the subsequent pregnancy. STUDY DESIGN: We conducted a retrospective nested cohort study of all cases with a histopathological finding of BPMF between August 2012 and March 2020 at a single tertiary referral center. Data were collected for all subjects (cases and controls) with at least two consecutive pregnancies (the initial index pregnancy and at least one subsequent pregnancy) accompanied by a concomitant record of histopathological study of the placenta at our center. The primary outcome was pathologically confirmed PAS in the subsequent pregnancy. Data are presented as percentage or median, interquartile range accordingly. RESULTS: A total of n = 1,344 participants were included, of which n = 119 (index cases) carried a contemporaneous histopathological diagnosis of BPMF during the index pregnancy and n = 1,225 did not (index controls). Among the index cases, patients with BPMF were older (31.0 [20, 42] vs. 29.0 [15, 43], p < 0.001), more likely to have undergone in vitro fertilization (IVF) for conception (10.9 vs. 3.8%, p = 0.001) and were of a more advanced gestational age at delivery (39.0 [25, 41] vs. 38.0 [20, 42], p = 0.006). In the subsequent pregnancy, the rate of PAS was significantly higher among the BPMF index cases (6.7 vs. 1.1%, p < 0.001). After adjusting for maternal age and IVF, a histopathological diagnosis of BPMF in an index pregnancy was shown to be a significant risk factor for PAS in the subsequent gestation (hazard ratio: 5.67 [95% confidence interval: 2.28, 14.06], p < 0.001). CONCLUSION: Our findings support that a histopathological diagnosis of BPMF is an independent risk factor for PAS in the subsequent pregnancy. KEY POINTS: · BPMF may indicate morbid adherence of placenta.. · Patients with BPMF were older and more likely to have undergone IVF for conception.. · The BPMF in the current pregnancy is an independent risk factor for PAS in the subsequent pregnancy..

Social Drivers of COVID-19 Disease Severity in Pregnant Patients.

OBJECTIVE: While coronavirus disease 2019 (COVID-19), the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has had global impact in all populations, certain groups of patients have experienced disproportionate rates of morbidity and mortality. The purpose of this study was to assess the relationship between COVID-19 disease severity, demographic variables, race and ethnicity, and social determinants of health among pregnant patients in a diverse urban population. STUDY DESIGN: A retrospective analysis was performed of all pregnant patients diagnosed with COVID-19 at two urban tertiary care centers in Houston, TX between March and August 2020. Maternal demographic, COVID-19 illness criteria, and delivery characteristics were collected. The Centers for Disease Control and Prevention Social Vulnerability Index (SVI) and COVID-19 Community Vulnerability Index (CCVI) were obtained based on a patients' census tract of residence. Analyses compared persons with asymptomatic, mild, or severe-critical disease at diagnosis. RESULTS: A total of 317 persons tested positive for COVID-19 during this time period. Asymptomatic persons were more likely to be diagnosed at later gestational ages, but there were no other differences in baseline maternal characteristics. Persons with more severe disease had greater social vulnerability specifically for housing and transportation than those with mild disease (mean SVI [standard error]: 0.72 [0.06] vs. 0.58 [0.2], p = 0.03). Total SVI, total CCVI, and other themed SVI and CCVI indices were not significantly different between groups. CONCLUSION: In this cohort of pregnant persons infected with SARS-CoV-2, an association was shown between disease severity and increased vulnerability in living conditions and transportation. Drivers of the pandemic and COVID-19 outcomes are complex and multifactorial, and likely change over time. However, continued efforts to accurately identify and measure social determinants of health in medicine will likely help identify geographic areas and patient populations that are at risk of higher disease burden. This could facilitate preventative and mitigation measures in these areas in future disaster or pandemic situations. KEY POINTS: · SVI and CCVI estimate social determinants of health.. · COVID-19 is associated with housing and transportation vulnerability.. · Social determinants contribute to disease burden in pregnancy..

Pregnancy outcomes following early fetoscopic laser photocoagulation for twin-to-twin transfusion syndrome at 16 weeks' gestation.

BACKGROUND: Ample evidence supports fetoscopic laser photocoagulation of placental anastomoses as a first-line treatment for twin-to-twin transfusion syndrome, but little is known about the outcomes following procedures conducted in the early second trimester. OBJECTIVE: This study aimed to evaluate perinatal outcomes following early fetoscopic laser placental photocoagulation performed for twin-to-twin transfusion syndrome at 16 weeks' gestation. STUDY DESIGN: This retrospective review included monochorionic twin pregnancies complicated by twin-to-twin transfusion syndrome necessitating fetoscopic laser photocoagulation at a single tertiary center from 2012 to 2021. The 2 cohorts were defined as cases undergoing laser surgery at 16+0/7 to 16+6/7 weeks' gestation (early laser group) and those undergoing laser surgery ≥17 weeks' gestation (standard laser group), respectively. Primary outcomes included rates of immediate chorioamniotic membrane separation, preterm premature rupture of membranes, and clinical chorioamnionitis. Secondary outcomes included twin survival rates at birth and 30 days of life. Outcomes were compared between cohorts with a P value of <.05 denoting statistical significance. RESULTS: A total of 343 cases were included (35 early laser participants and 308 standard laser participants). The early laser group typically had higher Quintero staging at the time of the procedure. Following intervention, the early laser group had significantly higher rates of chorioamniotic separation than the standard laser group (34.3% vs 1.3% of cases; P<.001) and higher rates of preterm prelabor rupture of membranes (45.7% vs 25.0%; P=.009) and chorioamnionitis (11.4% vs 1.3%; P=.005). Even after adjustment for higher Quintero staging in the early laser group, twin survival was not significantly different between study groups. CONCLUSION: Early laser surgery for twin-to-twin transfusion syndrome performed at 16 weeks' gestation is associated with significantly higher rates of chorioamniotic separation, preterm rupture of membranes, and chorioamnionitis. However, twin survival does not seem to be negatively impacted following early laser surgery.

Placenta Accreta Spectrum: Correlation between FIGO Clinical Classification and Histopathologic Findings.

OBJECTIVE: Placenta accreta spectrum (PAS) covers a wide spectrum of placental adherence/invasion with varied clinical significance. Histopathologic examination is considered the confirmatory gold standard, but is only obtained sometime after definitive treatment. The International Federation of Gynecology and Obstetrics (FIGO) has published a new clinical classification that can be assigned at delivery, and we aimed to investigate the association between this new FIGO classification and histopathology and also to assess its correlation with maternal outcomes. STUDY DESIGN: We studied a retrospective cohort of 185 patients with histopathologically proven PAS managed at our referral center between September 2012 and January 2019. Two experienced surgeons retrospectively reviewed charts and assigned the FIGO grading based on findings reported at delivery. A third experienced reviewer adjudicated to determine the classification used for final analysis. Categorical outcomes were compared with the use of chi-squared and the Fisher exact test, as appropriate. A multivariate model was designed to adjust outcomes in different FIGO groups for the involvement of a formal multidisciplinary management team. RESULTS: Among 185 patients, there were 41 (22%) placenta accreta, 44 (24%) placenta increta, and 100 (54%) placenta percreta on histopathology. The inter-rater reliability was found to be substantial with Kappa = 0.661 (p < 0.001), and 95% confidence interval (CI): 0.449-0.872. There was a significant association between all histopathology groupings and the FIGO clinical classification (p < 0.001). However, we found no association between FIGO classifications and maternal complications. CONCLUSION: The new FIGO clinical classification is strongly associated with histopathologic findings. A better understanding of the depth and extent of invasion as afforded by the clinical classification system will help standardize reporting and future research. KEY POINTS: · PAS includes a wide spectrum of placental invasion with varied clinical significance.. · Histopathological examination is considered the confirmatory gold standard.. · The new FIGO clinical classification is strongly associated with histopathologic findings..

The Association between Placenta Accreta Spectrum Severity and Incidence of Small for Gestational Age Neonates.

OBJECTIVE: The aim of the study is to evaluate whether pathologic severity of placenta accreta spectrum (PAS) is correlated with the incidence of small for gestational age (SGA) and neonatal birthweight. STUDY DESIGN: This was a multicenter cohort study of viable, non-anomalous, singleton gestations delivered with histology-proven PAS. Data including maternal history, neonatal birthweight, and placental pathology were collected and deidentified. Pathology was defined as accreta, increta, or percreta. The primary outcome was rate of SGA defined by birth weight less than the 10th percentile. The secondary outcomes included incidence of large for gestational age (LGA) babies as defined by birth weight greater than the 90th percentile as well as incidence of SGA and LGA in preterm and term gestations. Statistical analysis was performed using Chi-square, Kruskal-Wallis, and log-binomial regression. Increta and percreta patients were each compared with accreta patients. RESULTS: Among the cohort of 1,008 women from seven United States centers, 865 subjects were included in the analysis. The relative risk (RR) of SGA for increta and percreta did not differ from accreta after adjusting for confounders (adjusted RR = 0.63, 95% confidence interval [CI]: 0.36-1.10 for increta and aRR = 0.72, 95% CI: 0.45-1.16 for percreta). The results were stratified by placenta previa status, which did not affect results. There was no difference in incidence of LGA (p = 1.0) by PAS pathologic severity. The incidence of SGA for all PAS patients was 9.2% for those delivered preterm and 18.7% for those delivered at term (p = 0.004). The incidence of LGA for all PAS patients was 12.6% for those delivered preterm and 13.2% for those delivered at term (p = 0.8203). CONCLUSION: There was no difference in incidence of SGA or LGA when comparing accreta to increta or percreta patients regardless of previa status. Although we cannot suggest causation, our results suggest that PAS, regardless of pathologic severity, is not associated with pathologic fetal growth in the preterm period. KEY POINTS: · PAS severity is not associated with SGA in the preterm period.. · PAS severity is not associated with LGA.. · Placenta previa does not affect the incidence of SGA in women with PAS..

Massive Transfusion Protocols in Obstetric Hemorrhage: Theory versus Reality.

OBJECTIVE: Massive transfusion protocols are widely implemented in obstetrical practice in case of severe hemorrhage; however, different recommendations exist regarding the appropriate ratios of blood product components to be transfused. We report our extensive experience with massive component transfusion in a referral center in which the standard massive transfusion protocol is modified by ongoing clinical and laboratory evaluation. STUDY DESIGN: A retrospective chart review of all patients who had massive transfusion protocol activation in a level 4 referral center for obstetrical practice was performed from January 2014 to January 2020. Data collected included the etiology of obstetrical hemorrhage, number of blood products of each type transfused, crystalloid infusion, and several indices of maternal morbidity and mortality. Data are presented with descriptive statistics. RESULTS: A total of 62 patients had massive transfusion protocol activation, of which 97% received blood products. Uterine atony was found to be the most common etiology for massive hemorrhage (34%), followed by placenta accreta spectrum (32%). The mean estimated blood loss was 1,945 mL. A mean of 6.5 units of packed red blood cells, 14.8 units of fresh frozen plasma and cryoprecipitate, and 8.3 units of platelets were transfused per patient. No maternal deaths were seen. CONCLUSION: The ratios of transfused packed red blood cell to fresh frozen plasma/cryoprecipitate and of packed red blood cell to platelet units varied significantly from the fixed initial infusion ratio called for by our massive transfusion protocol resulting in universally favorable maternal outcomes. When rapid laboratory evaluation of hematologic and clotting parameters is available, careful use of this information may facilitate safe modification of an initial fixed transfusion ratio based on etiology of the hemorrhage and individual patient response. KEY POINTS: · Massive transfusion protocols in obstetrics follow fixed ratios of blood products.. · Actual usage of blood components is different than the standardized protocols.. · We recommend to modify the initial fixed transfusion ratio according to clinical response..

Clinical Correlates of Placenta Accreta Spectrum Disorder Depending on the Presence or Absence of Placenta Previa: A Systematic Review and Meta-analysis.

OBJECTIVE: To evaluate whether there are differences in risk factors and maternal outcomes of pregnancies complicated by placenta accreta spectrum depending on the presence or absence of placenta previa. DATA SOURCES: We performed a systematic search in Medline, EMBASE, ClinicalTrials.gov , and Web of Science from inception through April 25, 2022, without language or date restrictions. Search strategy included the key words "placenta accreta," "placenta increta," "placenta percreta," "adherent placenta," "invasive placenta," "abnormal placent*," "placenta previa," and "marginal placent*." METHODS OF STUDY SELECTION: Of the 1,122 articles screened, seven studies were included in the final review. Studies were included if they compared the risk factors and maternal outcomes of pregnancies complicated by placenta accreta spectrum depending on the presence or absence of placenta previa. TABULATION, INTEGRATION, AND RESULTS: A random-effects model was used to pool the mean differences or odds ratios (OR) and the corresponding 95% CIs using RevMan software. A total of 3,342 pregnancies complicated by placenta accreta spectrum were included in the meta-analysis (2,365 without previa and 977 with previa). Pregnancies complicated by placenta accreta spectrum without previa were more likely to have been conceived by in vitro fertilization (IVF) (OR 3.11, 95% CI 1.93-5.02, P <.001, I 2 =52.0%) and to be associated with prior dilation and curettage (D&C) (OR 1.60, 95% CI 1.15-2.22, P =.005, I 2 =0.0%) and myomectomy (OR 2.47, 95% CI 1.31-4.66, P =.005, I 2 =0.0%), but they were less likely to be associated with prior cesarean delivery (OR 0.15, 95% CI 0.06-0.37, P <.001, I 2 =87.0%). Placenta accreta spectrum without previa was less likely to be diagnosed antenatally (OR 0.07, 95% CI 0.04-0.11, P <.001, I 2 =38.0%). Also, women with pregnancies without previa had lower rates of red blood cell transfusion, intensive care unit admission, risk of hysterectomy, unscheduled delivery, and intraoperative bowel or bladder injuries. CONCLUSION: Pregnancies complicated by placenta accreta spectrum without previa had a more prominent association with IVF and prior D&C and myomectomy but were much less likely to be associated with prior cesarean delivery. Further, placenta accreta spectrum without previa was less likely to be diagnosed antenatally, although it had better maternal outcomes as compared with placenta accreta spectrum with previa. SYSTEMATIC REVIEW REGISTRATION: PROSPERO, CRD42022307637.

Timing of delivery for placenta accreta spectrum: the Pan-American Society for the Placenta Accreta Spectrum experience.

BACKGROUND: The Society for Maternal-Fetal Medicine recommends cesarean delivery with potential hysterectomy scheduled in the late preterm period between 34 0/7 and 35 6/7 weeks of gestation for prenatally suspected placenta accreta spectrum. OBJECTIVES: We aimed to investigate clinical compliance with the recommended delivery timing window for placenta accreta spectrum and its impact on maternal and neonatal outcomes. STUDY DESIGN: We performed a retrospective multicenter review of data from referral centers within the Pan-American Society for Placenta Accreta Spectrum. Patients with placenta accreta spectrum with both antenatal diagnosis and confirmed histopathologic findings were included. We investigated adherence to the Society for Maternal-Fetal Medicine-recommended gestational age window for delivery, and compliance was further stratified by scheduled and unscheduled delivery. We compared the outcomes for patients with scheduled delivery within vs immediately 2 weeks outside the recommended window. RESULTS: Among 744 patients with a prenatal diagnosis of placenta accreta spectrum and placental histopathologic confirmation, 488 (66%) had scheduled delivery. Among all prenatally diagnosed placenta accreta spectrum patients, 252 (39%) delivered within the recommended window of 34 0/7 and 35 6/7 weeks gestation. For the subgroup of patients who underwent scheduled delivery (n=426), 209 (49%) had delivery in this window, 120 (28%) delivered before 34 weeks, and 97 (23%) delivered at or later than 36 weeks. In the patients with scheduled delivery, 27% of placenta accreta spectrum patients with accreta delivered in the 2 weeks immediately after the recommended window (36 0/7-37 6/7 weeks), and 22% of placenta accreta spectrum pregnancies with increta/percreta delivered in the 2 weeks immediately before the recommended delivery (32 0/7-33 6/7 weeks). The maternal outcomes among those who delivered within the recommended range vs those delivering 2 weeks before and after the recommended range were similar, regardless of placenta accreta spectrum severity. CONCLUSION: Less than half of placenta accreta spectrum patients had scheduled delivery within the recommended gestational age of 34 0/7 to 35 6/7 weeks. The reasons for deviation from recommendations and the risks and benefits of individualized timing of delivery on the basis of risk factors and predicted outcomes warrant further investigation.

The Society for Pediatric Pathology Task Force grading system for placenta accreta spectrum and its correlation with clinical outcomes.

BACKGROUND: The terminology and diagnostic criteria presently used by pathologists to report placenta accreta spectrum is inconsistent and does not reflect current knowledge of the pathogenesis of this disease. OBJECTIVE: In 2020, the perinatal subcommittee of the Society for Pediatric Pathology Placenta Accreta Task Force proposed a new pathologic grading system for placenta accreta spectrum. We sought to correlate the clinical outcomes with the classification into each group in the new placenta accreta spectrum grading system. STUDY DESIGN: The pathology reports of patients with histopathologic confirmation of placenta accreta spectrum were reviewed in 2 academic referral centers by placental pathologists. Pathologic grading was assigned based on the new grading system according to which placenta accreta spectrum is categorized into 5 groups depending on the depth of invasion, from grade p1 with no invasion into the uterine wall to grade p3E with invasion beyond the uterine wall to the adjacent organs. Patient characteristics and clinical outcomes were compared among these groups. A univariate analysis was performed, and a multivariate linear or binomial regression was employed when needed. RESULTS: A total of 683 patients with placenta accreta spectrum were identified. Of those, 407 were included for histology review. There were 92 patients (23%) categorized into the grade p1 group, 74 (18%) in the grade p2 group, 84 (20%) in the grade p3A group, 121 (30%) in the grade p3D group, and 36 (9%) in the grade p3E group. There was a significant association between the pathology grading and the number of red blood cells transfused (ß=1.14; 95% confidence interval, 0.48-1.79) and the postoperative complications including the rate of readmission (risk ratio, 1.93; 95% confidence interval, 1.26-2.94) and bladder injury (risk ratio, 1.81; 95% confidence interval, 1.23-2.68) after adjustment for antenatal diagnosis and other variables. The pathology grading was not associated with the estimated blood loss (P=.072). CONCLUSION: The new pathology grading system accurately reflects maternal outcomes and complications of placenta accreta spectrum. We encourage the utilization of this new pathologic grading system because it is designed to omit discrepancies in placenta accreta spectrum reporting and to standardize communication.

The impact of response to iron therapy on maternal and neonatal outcomes among pregnant women with anemia.

BACKGROUND: Anemia during pregnancy is associated with increased risks of preterm birth, preeclampsia, cesarean delivery, and maternal morbidity. The most prevalent modifiable cause of pregnancy-associated anemia is iron deficiency. However, it is still unclear whether iron therapy can reduce the risks of adverse outcomes in women with anemia. OBJECTIVE: This study aimed to determine whether response to iron therapy among women with anemia is associated with a change in odds of adverse maternal and neonatal outcomes. STUDY DESIGN: This was a population-based cohort study (2011-2019) using an institutional database composed of obstetrical patients from 2 delivery hospitals. Patients with adequate prenatal care were classified as being anemic or nonanemic (reference). Patients with anemia were further stratified by success or failure of treatment with oral iron therapy using the American College of Obstetricians and Gynecologists criteria for anemia at the time of admission for delivery: successfully treated (Hgb≥11 g/dL) or unsuccessfully treated ("refractory;" Hgb<11 g/dL). All categories of women with anemia categories were compared with the reference group of women without anemia using chi-square and logistic regression analyses. The primary outcomes were preterm birth and preeclampsia. RESULTS: Among the 20,690 women observed, 7416 (35.8%) were anemic. Among women with anemia, 1319 (17.8%) were refractory to iron therapy, 2695 (36.3%) had a successful response to therapy, and 3402 (45.9%) were untreated. Successfully treated patients with anemia had a significant reduction in the odds of preterm birth (5.1% vs 8.3%; adjusted odds ratio, 0.59; 95% confidence interval, 0.47-0.72) and preeclampsia (5.9% vs 8.3%; adjusted odds ratio, 0.75; 95% confidence interval, 0.61-0.91). Refractory and untreated patients had significantly increased odds of preterm birth (adjusted odds ratio, 1.44 [95% confidence interval, 1.16-1.76] and 1.45 [95% confidence interval, 1.26-1.67], respectively) and preeclampsia (adjusted odds ratio, 1.54 [95% confidence interval, 1.24-1.89] and 1.44 [95% confidence interval, 1.25-1.67], respectively). All groups of women with anemia had increased odds of postpartum hemorrhage and decreased odds of delivering a small for gestational age neonate. There was no difference in composite neonatal morbidity. CONCLUSION: Successful treatment of anemia with oral iron therapy was associated with a reduction in the odds of preterm birth and preeclampsia. Women with refractory anemia had similar outcomes to those who were untreated, emphasizing the importance of monitoring response to iron therapy during pregnancy.

Urologic morbidity associated with placenta accreta spectrum surgeries: single-center experience with a multidisciplinary team.

BACKGROUND: Hysterectomy for placenta accreta spectrum may be associated with urologic morbidity, including intentional or unintentional cystostomy, ureteral injury, and bladder fistula. Although previous retrospective studies have shown an association between placenta accreta spectrum and urologic morbidities, there is still a paucity of literature addressing these urologic complications. OBJECTIVE: We sought to report a systematic description of such morbidity and associated factors. STUDY DESIGN: This was a retrospective study of all histology-proven placenta accreta spectrum deliveries in an academic center between 2011 and 2020. Urologic morbidity was defined as the presence of at least one of the following: cystotomy, ureteral injury, or bladder fistula. Variables were reported as median (interquartile range) or number (percentage). Analyses were made using appropriate parametric and nonparametric tests. Multinomial regression analysis was performed to assess the association of adverse urologic events with the depth of placental invasion. RESULTS: In this study, 58 of 292 patients (19.9%) experienced urologic morbidity. Patients with urologic morbidity had a higher rate of placenta percreta (compared with placenta accreta and placenta increta) than those without such injuries. Preoperative ureteral stents were placed in 54 patients (93.1%) with and 146 patients (62.4%) without urologic injury (P=.003). After adjusting for confounding variables, multinomial regression analysis revealed that the odds of having adverse urologic events was 6.5 times higher in patients with placenta percreta than in patients with placenta accreta. CONCLUSION: Greater depth of invasion in placenta accreta spectrum was associated with more frequent and severe adverse urologic events. Whether stent placement confers any protective benefit requires further investigation.

Clinical Outcomes of a False-Positive Antenatal Diagnosis of Placenta Accreta Spectrum.

OBJECTIVE: Antenatal diagnosis of placenta accreta spectrum (PAS) is critical to reduce maternal morbidity. While clinical outcomes of women with PAS have been extensively described, little information is available regarding the women who undergo cesarean delivery with a presumptive PAS diagnosis that is not confirmed by histopathologic examination. We sought to examine resource utilization and clinical outcomes of this group of women with a false-positive diagnosis of PAS. STUDY DESIGN: This is a retrospective analysis of patients with prenatally diagnosed PAS cared for between 2015 and 2020 by our multidisciplinary PAS team. Maternal outcomes were examined. Univariate analysis was performed and a multivariate model was employed to compare outcomes between women with and without histopathologically confirmed PAS. RESULTS: A total of 162 patients delivered with the preoperative diagnosis of PAS. Of these, 146 (90%) underwent hysterectomy and had histopathologic confirmation of PAS. Thirteen women did not undergo the planned hysterectomy. Three women underwent hysterectomy but pathologic examination did not confirm PAS. In comparing women with and without pathologic confirmation of PAS, the false-positive PAS group delivered later in pregnancy (34 vs. 33 weeks of gestation, p = 0.015) and had more planned surgery (88 vs. 47%, p = 0.002). There was no difference in skin incision type or hysterotomy placement for delivery. No significant difference in either the estimated blood loss or blood components transfused was noted between groups. CONCLUSION: Careful intraoperative evaluation of women with preoperatively presumed PAS resulted in a 3/149 (2%) retrospectively unnecessary hysterectomy. Management of women with PAS in experienced centers benefits patients in terms of both resource utilization and avoidance of unnecessary maternal morbidity, understanding that our results are produced in a center of excellence for PAS. We also propose a management protocol to assist in the avoidance of unnecessary hysterectomy in women with the preoperative diagnosis of PAS. KEY POINTS: · Evaluation and delivery planning of patients with suspected placenta accreta spectrum in experienced centers provides acceptable outcomes.. · Under specific circumstances, delivery of placenta may be attempted if placenta accreta is suspected.. · Patients with suspected placenta accreta rarely undergo unindicated hysterectomy..

Relationship Between Umbilical Cord Gas Values and Neonatal Outcomes: Implications for Electronic Fetal Heart Rate Monitoring.

OBJECTIVE: To evaluate the relationship between umbilical artery cord gas values and fetal tolerance of labor, as reflected by Apgar score. We hypothesized the existence of wide biological variability in fetal tolerance of metabolic acidemia, which, if present, would weaken one fundamental assumption underlying the use of electronic fetal heart rate (FHR) monitoring. METHODS: We conducted a retrospective cohort study of term, singleton, nonanomalous fetuses delivered in our institution between March 2012 and July 2020. Universally obtained umbilical cord gas values and Apgar scores were extracted. We calculated Spearman correlation coefficients and receiver operating characteristic curves for various levels of umbilical artery pH, base excess, and Apgar scores. RESULTS: We analyzed data from 29,787 deliveries. The statistical correlation between umbilical artery pH and base excess and both 1- and 5-minute Apgar scores was weak or nonexistent in all pH range subgroups (range 0.064-0.213). Receiver operating characteristic curve analysis suggested umbilical artery pH value of 7.22 yields the best discrimination for prediction of a severely depressed newborn (5-minute Apgar score less than 4), but sensitivity and specificity for this predictive value remains poor to moderate. CONCLUSION: The use of electronic FHR monitoring is predicated on a documented relationship between FHR patterns and umbilical artery pH, and an assumed correlation between pH and fetal outcomes, reflecting fetal tolerance of labor and delivery. Our data demonstrate a weak-to-absent correlation between metabolic acidemia and even short-term fetal condition, thus significantly weakening this latter assumption. No amount of future modification of FHR pattern interpretation to better predict newborn pH is likely to lead to improved newborn outcomes, given this weakness in a fundamental assumption on which FHR monitoring is based.

In vitro fertilization as an independent risk factor for placenta accreta spectrum.

BACKGROUND: Placenta accreta spectrum is well known for its association with catastrophic maternal outcomes. However, its pathophysiology is not well defined. There have been emerging data that in vitro fertilization may be a risk factor for placenta accreta spectrum. OBJECTIVE: We investigated the hypothesis that in vitro fertilization is an independent risk factor for placenta accreta spectrum. STUDY DESIGN: A retrospective analysis of all deliveries in a prospective, population-based cohort (2012-2019) was performed in a tertiary academic center. Primary outcome variable was placenta accreta spectrum. Univariate analysis was performed on potential risk factors for predicting placenta accreta spectrum, and a multivariate model was designed to best fit the prediction of placenta accreta spectrum adjusted for risk factors such as cesarean delivery, placenta previa, age, and parity. History of previous cesarean delivery was known as a risk factor for both placenta previa and placenta accreta spectrum; hence, the interaction between "placenta previa" and "previous cesarean delivery" was included in the final model. Odds ratios were calculated as exponential of beta coefficients from the multivariate regression analysis. RESULTS: A total of 37,461 deliveries were included in this analysis, 5464 (15%) of which had a history of cesarean delivery, 281 (0.7%) had placenta previa in their index pregnancy, and 571 (1.5%) had in vitro fertilization pregnancy. The frequency of placenta accreta spectrum was 230 (0.6%). Independent risk factors for placenta accreta spectrum were in vitro fertilization pregnancy (adjusted odds ratio, 8.7; 95% confidence interval, 3.8-20.3), history of previous cesarean delivery (adjusted odds ratio, 21.1; 95% confidence interval, 11.4-39.2), and presence of placenta previa (adjusted odds ratio, 94.6; 95% confidence interval, 29.3-305.1). After adjustment for number of previous cesarean deliveries, the correlation persisted for in vitro fertilization (adjusted odds ratio, 6.7; 95% confidence interval, 2.9-15.6). CONCLUSION: Our data suggested that in vitro fertilization is an independent risk factor for placenta accreta spectrum, although its relative clinical importance compared with that of the presence of placenta previa and history of cesarean delivery is small. The pathophysiology behind this relationship remains to be investigated.