Risk Of Placenta Accreta Spectrum Research Articles

Impact of a standardized multidisciplinary protocol for placenta accreta spectrum on blood bank services

To assess the impact of a standardized multidisciplinary protocol for managing patients with placenta accreta spectrum (PAS) on the utilization of blood bank services. We performed a retrospective cohort study of all pregnant women managed at our center between January 2013 and October 2019 for confirmed or suspected PAS disorders. We compared the demographic and clinical characteristics of the patients and the utilization of blood bank services, including dispensed, transfused, and wasted blood components products, before (T1) and after (T2) the implementation of a standardized multidisciplinary protocol. This protocol focused on increased surveillance and readiness for patients at risk for PAS, standardization of surgery, anesthesia and transfusion practices, selective embolization of pelvic arteries in patients with abnormally invasive placenta, intraoperative blood salvage, and robust treatment of anemia antenatally. Univariate analysis was performed using unpaired t, Mann-Whitney, chi-square, and Fisher's exact tests as appropriate. The patients' characteristics in T1 and T2 were comparable (Table1). In T2, 79% of the patients were managed according to the protocol. The number of blood products dispensed from the blood bank, particularly RBCs, increased during T2. (Table 2). In contrast, fewer RBCs and FFPs were transfused in T2. There was no significant difference in dispensed or transfused platelet and cryoprecipitate units. The number of wasted blood products was small and did not significantly change. The decreased transfusion of RBC and FFP was the result of a decline in peripartum blood loss (median, 800 vs.1550 ml, p< . 001) and the risk for massive blood loss (RR: 0.16, 95% CI: 0.03 to 0.92, p=.04) and stage 3 postpartum hemorrhage (RR: 0.37, 95% CI: 0.17 to 0.75, p=.009). The standardized multidisciplinary protocol for PAS increased the workload of our blood bank due to greater dispensation of blood products but resulted in fewer RBC and FFP transfusions parallel to a decline in catastrophic hemorrhage.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Normal placental structural anatomy: ultrasound and doppler features elucidated with US-MR image fusion and ferumoxytol-enhanced MRI.

To elucidate ultrasound features of normal placental anatomy through correlation of gray-scale and ultrasound Doppler with ferumoxytol-enhanced MRI features using US-MR image fusion. All patients referred to MR for ultrasound findings worrisome for PAS (placenta accreta spectrum) were included in this retrospective study. MR studies included a ferumoxytol-enhanced T1-weighted MRI. Ultrasound imaging included gray-scale, color Doppler, power Doppler, and spectral Doppler techniques. After the MR, US-MRI fusion was performed by co-registering a MR acquisition to real-time US, which allowed precise, point-to-point correlation of placental features. Fourteen patients at risk for PAS were studied using the US-MR image fusion. At delivery, there were six cases without PAS (gestational age range: 24weeks 3days to 34weeks 0days), and these composed the study cohort. Placental features that were on high signal intensity on post-ferumoxytol acquisitions represent spaces with maternal blood flow and corresponded to hypoechoic areas on ultrasound created by a paucity of reflective interfaces (villi). Color and spectral Doppler allowed the separation of maternal and fetal circulations in individual perfusional domains and demonstrated spiral artery inflow, circulation around the villous tree, and return of blood flow to the basal plate. Recognizable histopathologic features by ultrasound included the central cavity, villous tree, and venous return channels. Internal placental architecture can be discerned on ultrasound. This anatomy can be correlated and confirmed with ferumoxytol-MR through US-MR fusion. Understanding this structural anatomy on ultrasound could serve as a basis to identify normal and abnormal placental features.

The impact of preoperative ultrasound and intraoperative findings on surgical outcomes in patients at high risk of placenta accreta spectrum.

To assess whether preoperative ultrasound imaging and intraoperative features predict surgical outcomes in patients at high risk for placenta accreta spectrum (PAS). Cohort study. Cairo University Maternity, Egypt. Pregnant patients with one or more prior caesarean deliveries presenting with a low-lying/placenta praevia with or without PAS confirmed by histopathology. Logistic regression and multivariable analyses. Need for primary caesarean hysterectomy, numbers of red blood cell (RBC) units transfused and patients requiring transfusion of >5units. Ninety consecutive records were reviewed, including 58 (64.4%) PAS cases. Sixty (66.7%, 95% confidence interval (CI) 56-76) required hysterectomy. Odds of hysterectomy were significantly (p= 0.005) increased with complete praevia. Significantly higher odds of hysterectomy were associated with subplacental hypervascularity (7.23, 95% CI 2.72-19.2, p< 0.001), lacunar scores 2+ and 3+ (12.6, 95% CI 4.15-38.5, p< 0.001), lacunar feeder vessels (5.69, 95% CI 1.77-18.3, p= 0.004) or bridging vessels (2.00, 95% CI 1.29-3.10, p= 0.002) on ultrasound, and increased lower segment vascularization at laparotomy (5.42, 95%CI 2.09-14.1, p= 0.001). Transfusion >5 RBC units was associated with number of lacunae (odds ratio [OR] 1.48, 95% CI 1.14-1.93, p= 0.004) and presence of feeder vessels (OR 1.62, 95% CI 1.24-2.11, p= 0.001). The multivariable analysis indicated that parity, placental location and PAS were significantly (p= 0.007; p= 0.01; p< 0.001, respectively) associated with hysterectomy. Preoperative ultrasound imaging can assist in triaging and counselling patients regarding the odds of PAS, intraoperative blood losses and need for hysterectomy, and intraoperative features can assist the surgeon in evaluating the need for multidisciplinary support.

Separation sign: novel ultrasound sign for ruling out diagnosis of placenta accreta spectrum.

ABSTRACTObjectiveTo assess the performance of the ‘separation sign’ as a predictor of normal placental separation in a large cohort of women at risk for placenta accreta spectrum (PAS) and in a high‐risk subgroup with placenta previa or anterior low‐lying placenta and at least one previous Cesarean delivery.MethodsThis was a prospective study of women at risk for PAS referred to a specialist clinic at between 22 and 38 weeks' gestation. All women underwent ultrasound assessment for the presence of the separation sign, which detects the difference in elasticity between the myometrium and the placenta, characterized by different rates of rebound after an ultrasound probe is used to apply pressure over the uteroplacental interface. When the sign is positive, the placenta appears to move relative to the myometrium, leading to the appearance or enhancement of the clear zone. The predictive performance of the separation sign for normal spontaneous placental separation at delivery was assessed.ResultsOf the 194 included women, 163 had a positive separation sign, all of whom went on to have normal placental separation at delivery. Of the 24 women with a negative separation sign, three (12.5%) had normal placental separation and 21 (87.5%) were diagnosed with PAS. This yielded a sensitivity of 98.2% (95% CI, 94.8–99.6%) and specificity of 100% (95% CI, 83.9–100%). In the high‐risk cohort (n = 35), a positive separation sign remained a reliable predictor of normal placental separation, with a positive predictive value of 100%, sensitivity of 88.9% (95% CI, 65.3–98.6%) and specificity of 100% (95% CI, 80.5–100%).ConclusionsThe separation sign could be a useful tool in women considered to be at risk for PAS, as it can facilitate the prediction of normal placental separation at delivery. This may prevent overtreatment, the associated iatrogenic morbidity and unnecessary allocation of clinical resources. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Maternal Smoking and the Risk of Placenta Accreta Spectrum: A Systematic Review and Meta-Analysis.

Background This is the first meta-analysis that assessed the association between maternal smoking and the risk of placenta accreta spectrum (PAS), so this study was aimed at investigating the association between maternal smoking and PAS based on observational studies. PAS is defined as a severe obstetric complication due to the abnormal invasion of the chorionic villi into the myometrium and uterine serosa. Methods We searched electronic bibliographic databases including PubMed, Web of Science, Scopus, Science Direct, and Google Scholar until January 2022. The results were reported using a random effect model. The chi-square test and the I2 statistic were used to assess heterogeneity. Egger's and Begg's tests were used to examine the probability of publication bias. All statistical analyses were performed at a significance level of 0.05 using Stata software, version 11. Results Based on the random effect model, the estimated OR of the risk of PAS associated with smoking was 1.21 (95% CI: 1.02, 1.41; I2 = 4.7%). Subgroup analysis was conducted based on study design, and the result showed that the association between smoking and PAS among cohort studies was significant 1.35 (95% CI: 1.15, 1.55; I2 = 0.0%). Conclusion Our results suggested that maternal smoking is a risk factor for the PAS. There was no heterogeneity among studies that reported an association between smoking and the PAS. The Newcastle-Ottawa Scale (NOS) was used to measure study quality.

The MRI estimations of placental thickness and cervical length correlate with postpartum hemorrhage (PPH) in patients with risk for placenta accreta spectrum (PAS) disorders

IntroductionThis study aims to identify whether placental thickness and cervical length measured by MRI correlate with postpartum hemorrhage (PPH) in patients at high risk for placenta accreta spectrum (PAS) disorders. MethodsThe placental thickness and cervical length of 200 patients from October 2017 to October 2021 were retrospectively measured. The mid-sagittal plane of the placentas was measured by 2 independent radiologists using MRI. Partial correlation analysis was used to characterize the correlation between placental thickness, cervical length and estimated blood loss during surgery. The correlation between clinical features, placental thickness, cervical length and PPH was evaluated with univariate and multivariate analyses. A nomogram was constructed based on the logistic regression. ResultsPlacental thickness was positively correlated with the estimated blood loss during delivery, while cervical length had a negative correlation with it, based on the adjustment for gestational age. Multivariate analyses revealed that prior cesarean section, placenta previa, increased placental thickness(≧4.35 cm) and short cervical length（< 3.05 cm） were independent risk factors for PPH. When the 4 risk factors were combined together, the AUC was the highest, 0.773 (95%CI 0.707–0.840). DiscussionPlacental thickness and cervical length correlated with PPH. The nomogram constructed based on prior cesarean section, placenta previa, placental thickness and cervical length can be used to recognize patients with a higher risk of PPH.

Placenta Accreta Spectrum Among Multiple Gestation: A Retrospective Analysis Based on a Chinese Population.

BackgroundIt remained controversial whether women with multiple gestation are at higher risk of placenta accreta spectrum (PAS) disorders and large-scale studies are needed. This study aimed to assess whether PAS incidence is higher among women with multiple gestation than among singleton, as well as to compare the characteristics and outcomes of PAS in multiple and singleton gestation.MethodsWomen who underwent cesarean section with live births at Peking University First Hospital from January 2015 to December 2020 were included. Demographic and clinical information was collected through chart review. Logistic regression models were used to analyze the associations between multiple gestation and PAS. The clinical characteristics and perioperative outcomes of PAS in multiple and singleton gestation were further compared.ResultsAmong the 14583 women included, 2.4% (352/14583) were diagnosed with PAS. PAS was slightly more prevalent among multiple gestations than among singletons (2.5% vs 2.4%, P=0.857). After adjusting for known risk factors and pregnancy complications, multiple gestation was associated with a higher risk of PAS (aOR=1.63, 95% CI 1.01-2.62). Among PAS patients, women who had multiple births had a significantly lower rate of previous cesarean deliveries (27.6% vs. 56.3%, P=0.003), placenta previa (17.2% vs. 56.3%, P<0.001) and invasive PAS (24.1% vs. 53.9, P=0.002) than singletons. There were no significant differences in perioperative outcomes between these two groups.ConclusionMultiple gestation could be independently associated with an elevated risk of PAS. The clinical characteristics of PAS in the multiple and singleton gestation groups differed significantly in cesarean delivery history and placenta previa. The results of this study may inform guidelines on the screening, early detection and timely intervention of PAS patients among women with multiple births.

Association between short interpregnancy interval and placenta accreta spectrum

BACKGROUNDThe incidence of placenta accreta spectrum is increasing in parallel with the growing number of cesarean deliveries performed. A shorter interpregnancy interval following cesarean delivery may prevent adequate scar healing, which could impact the risk of placenta accreta spectrum.OBJECTIVEWe aimed to investigate the association between short interpregnancy intervals and placenta accreta spectrum.STUDY DESIGNWe conducted a retrospective cohort study of patients at risk for placenta accreta spectrum at a tertiary academic center between 2002 and 2020. Our cohort was defined as pregnant individuals at risk for placenta accreta spectrum meeting the following criteria: placenta previa with previous cesarean delivery and/or uterine surgery, anterior low-lying placenta with previous cesarean delivery and/or uterine surgery, ≥3 previous cesarean deliveries, or any previous cesarean delivery with sonographic findings suspicious for placenta accreta spectrum. The primary outcome was surgically or histopathologically confirmed placenta accreta spectrum. Short interpregnancy interval was defined as <18 completed months from previous delivery and last menstrual period of the index pregnancy. Univariable analyses were performed with chi-square and Student's t-test, as appropriate, and Kruskal–Wallis for nonparametric variables. The unadjusted and adjusted odds ratios were calculated using multivariate logistic regression models. Covariates were selected if P<.2 in univariable analyses or defined a priori as clinically meaningful. The final models were derived using reverse stepwise selection of variables. We used Stata Statistical Software, version 15 (StataCorp, College Station, TX) to perform descriptive statistics.RESULTSOf 262 patients at risk of placenta accreta spectrum with complete records, 112 (42.7%) had placenta accreta spectrum. Pregnant individuals with short interpregnancy intervals of <18 months were no more likely than those with optimal interpregnancy intervals to have previa (58% [46/80] vs 46% [84/182]; P=.09) or placenta accreta spectrum (49% [39/80] vs 40% [73/182]; P=.19). Short interpregnancy interval of <18 months was not associated with placenta accreta spectrum (unadjusted odds ratio, 1.06; 95% confidence interval, 0.62–1.80). This association did not change when adjusting for previa and number of previous cesarean deliveries (adjusted odds ratio, 1.04; 95% confidence interval, 0.51–2.15). In a secondary analysis, an interpregnancy interval of <12 months was also not associated with placenta accreta spectrum (unadjusted odds ratio, 0.79; 95% confidence interval, 0.04–1.56; adjusted odds ratio, 0.52; 95% confidence interval, 0.21–1.27).CONCLUSIONIn patients at risk for placenta accreta spectrum, short interpregnancy intervals of <18 months or <12 months were not associated with placenta accreta spectrum, even when controlling for number of previous cesarean deliveries and previa. Short interpregnancy interval is not likely to be an important modifiable independent risk factor for placenta accreta spectrum.

"The Killer Placenta" - a threat to the lives of young women giving birth by cesarean section.

It is necessary to create a universal algorithm for the management of placenta accreta spectrum in order to minimize morbidity and mortality in young patients giving birth by caesarean section. This was a retrospective study of seven women before the age of 30 selected out of larger group of 40 pregnant patients. The patients were hospitalized in the Clinical Department of Perinatology, Gynecology and Obstetrics in Ruda Śląska, which is a 3rd level reference department. The inclusion criterion was the suspicion of placent accreta spectrum, based on clinical condition, ultrasound examination and magnetic resonance imaging. A patient with a diagnosed placenta accreta spectrum should be provided with a highly specialized 3rd level referential center by an experienced multidisciplinary team of specialists. There should be free access to the blood bank, adult intensive care unit and neonatal intensive care unit. According to the results of this study, the recommended time of cesarean section is 34 + 0 - 36 + 6 weeks of pregnancy. Hysterectomy after the cesarean section is a method of choice for a placenta increta or percreta. It is the most difficult surgery in obstetrics, with a high risk of intraoperative complications. Damage to the urinary system is the most common complication of perinatal hysterectomy. Preoperative placement of ureteral catheters reduces the risk of intraoperative damage. It is necessary to plan individual procedure for women who has low-lying or previa placenta, and who has history of prior cesarean section - in this group the risk of placenta accreta spectrum is higher.

Lower uterine segment scar assessment at 11-14 weeks' gestation to screen for placenta accreta spectrum in women with prior Cesarean delivery.

To validate prospectively transvaginal ultrasound assessment of the lower uterine segment (LUS) scar at the time of first-trimester screening in women with previous Cesarean section (CS) and to determine its feasibility and accuracy in stratifying women according to the risk for placenta accreta spectrum (PAS) disorder. Women with a history of CS were recruited between 11 + 0 and 13 + 6 weeks' gestation and underwent LUS scar assessment using transvaginal ultrasound. A standardized midsagittal plane, which included the cervicoisthmic canal (CIC), the uterine scar and the placental site, was obtained. The scar was described in terms of its size (narrow or dehiscent) and its location in relation to the CIC (within or above), with each LUS scar classified into one of four groups based on these features. Placental location was assessed and classified as high- or low-lying. Women were stratified according to the risk of PAS, based on the relationship between the scar location and placental site. Women were considered high risk when the scar was above the CIC and the placenta was low-lying (i.e. when the placenta was overlying an exposed scar) and low risk when the scar was within the CIC and/or the placenta was high. High-risk patients were followed up at 20 weeks and 28-30 weeks for the development of PAS. Maternal demographics, detailed obstetric history and obstetric outcome were collected. First-trimester transvaginal ultrasound was offered to 535 women with prior CS during the study period. A LUS scar was visualized in 79.9% (401/502) of those who agreed to undergo the examination. At this scan, the LUS scar was above the CIC in 9.0% (36/401) of women, but only 5.7% (23/401)additionally had a low-lying placenta overlying the scar. Of these 23 high-risk women, two were found to have PAS on the mid-trimester screening scan and one was noted to have placental adherence during evacuation following mid-trimester termination of pregnancy. On the first-trimester scan, 94.3% (378/401) of women were at low risk of PAS. This screening protocol yielded a positive likelihood ratio of 21.33 (95% CI, 13.02-34.96), sensitivity of 100% (95% CI, 29.24-100%), specificity of 95.31% (95% CI, 92.39-97.35%), positive predictive value of 16.7% (95% CI, 5.8-39.2%) and negative predictive value of 100% (95% CI, 98.4-100%). On multivariable regression analysis performed to identify confounding variables associated with a LUS scar above the CIC, only maternal body mass index ≥ 30 kg/m2 was significant (odds ratio (OR), 2.42 (95% CI, 1.04-5.39); P = 0.03). Although there was a trend towards an increased risk of a LUS scar above the CIC in women with prior elective prelabor CS (OR, 1.72 (95% CI, 0.80-3.68)), this association did not reach statistical significance. Routine transvaginal ultrasound assessment of the location of the LUS scar and placenta at the time of first-trimester screening between 11 + 0 and 13 + 6 weeks' gestation in women with prior CS is a feasible and effective tool to identify those at risk of subsequent development of PAS disorder. A finding of placental implantation over an exposed LUS scar seems to be cardinal in predicting the risk of PAS disorder in women with prior CS, with an excellent negative predictive value. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

The potential risk factors of placenta increta and the role of octamethylcyclotetrasiloxane.

The study aimed to investigate the potential risk factors for the placenta accreta spectrum (PAS), determine the predictive value of a diagnostic model, and evaluate the effects of octamethylcyclotetrasiloxane (OMCTS) on trophoblast proliferation and migration. This case-control study included 244 pregnant women with PAS and 327 normal pregnant women who visited Guangzhou Women and Children's Medical Centre, China, from January 2014 to December 2017. Blood was collected from 42 women with PAS and 77 controls, and plasma specimens were analyzed by gas chromatography-time-of-flight mass spectrometry. In addition, the proliferation and migration of trophoblast cells were examined after treatment with OMCTS. We found an association between the risk of PAS and clinical factors related to fasting blood glucose levels (BS0, OR = 5.78), as well as factors related to endometrial injury [history of cesarean section (OR = 179.59), uterine scarring (OR = 68.37), and history of abortion (OR = 5.66)]. Equally important, pregnant women with PAS had significantly higher plasma OMCTS concentrations than controls. In vitro, we found that OMCTS could promote the proliferation and migration of HTR8/SVneo cells. The model of combining clinical factors and OMCTS had a good performance in PAS prediction (AUC = 0.97, 95% CI 0.78-0.93). The early diagnosis of PAS in pregnant women requires assessing risk factors, metabolic status, and BS0 levels before 20weeks of gestation. OMCTS may be related to the development of PAS by promoting trophoblast cell proliferation and migration.

PLACENTA PREVIA AND PLACENTA ACCRETA SPECTRUM (PAS) DISORDER: INCIDENCE, RISK FACTOR AND FETOMATERNAL OUTCOME IN A TERTIARY CARE CENTER

Introduction: Placenta Previa is characterised by Placental implantation into the lower uterine segment covering whole or part of the cervix . It complicates 0.4% of pregnancy at term The average incidence is 0.3% or 1 case per 300 to 400 deliveries. The presence of placenta previa can also increase a woman's risk for placenta accreta spectrum (PAS). This spectrum of conditions includes placenta accreta, increta, and percreta. Uncontrolled postpartum hemorrhage from placenta previa or PAS may necessitate a blood transfusion, hysterectomy thus leaving the patient infertile, admission to the ICU, or even death. Material and method: Study was conducted in department of obstetrics &amp; gynecology , swaroop rani hospital, Allahabad for 1 year . A total of 102 pregnant women presenting to antenatal OPD or admitted in IPD with history of antepartum hemorrhage and conrmed case of PP or MAP in Ultrasonography were selected. The follow up till the fetomaternal outcome was done and risk factors were evaluated for 102 cases. Result: Out of the total 2342 deliveries in one year 95 patients had PP and the incidence was 4.04% and 7 patients had morbidily adherent Placenta which accounts to an incidence of 0.29%. Previous LSCS, Multiparity, increase maternal age, Dialatation and curettage were risk factors in both Placenta Previa and Morbidily Adherent Placenta. Antenatal complication were antepartum hemmorrhage , Anemia, preterm labor. Emergency LSCS is more common mode of delivery in cases of Placenta previa. Caesarean hysterectomy were done in 3.2% cases of Placenta Previa and all cases of Morbidily adherent placenta . Most common perinatal complications in both groups were prematurity and low birth weight. Conclusion: Now a days Placenta previa and Morbidily adherent placenta are very common. Incidence increases as the rate of cesaerean section or abdominal surgery were increases.Earlydiagnosis and pre plan mode of delivery will decrease the risk of prematurity and low birth weight.

Maternal age at first cesarean delivery related to adverse pregnancy outcomes in a second cesarean delivery: a multicenter, historical, cross-sectional cohort study

BackgroundTo determine the effects of maternal age at first cesarean on maternal complications and adverse outcomes of pregnancy with the second cesarean.MethodsThis was a multicenter, historical, cross-sectional cohort study involving singleton pregnancies ≥28 gestational weeks, with a history of 1 cesarean delivery, and who underwent a second cesarean between January and December 2017 at 11 public tertiary hospitals in 7 provinces of China. We analyzed the effects of maternal age at first cesarean on adverse outcomes of pregnancy in the second cesarean using multivariate logistic regression analysis.ResultsThe study consisted of 10,206 singleton pregnancies. Women were at first cesarean between 18 and 24, 25–29, 30–34, and ≥ 35 years of age; and numbered 2711, 5524, 1751, and 220 cases, respectively. Maternal age between 18 and 24 years at first cesarean increased the risk of placenta accreta spectrum (aOR, 1.499; 95% CI, 1.12–2.01), placenta previa (aOR, 1.349; 95% CI, 1.07–1.70), intrahepatic cholestasis of pregnancy (aOR, 1.947; 95% CI, 1.24–3.07), postpartum hemorrhage (aOR, 1.505; 95% CI, 1.05–2.16), and blood transfusion (aOR, 1.517; 95% CI, 1.21–1.91) in the second cesarean compared with the reference group (aged 25–29 years). In addition, maternal age ≥ 35 years at first cesarean was a risk factor for premature rupture of membranes (aOR, 1.556; 95% CI, 1.08–2.24), placental abruption (aOR, 6.464, 95% CI, 1.33–31.51), uterine rupture (aOR, 7.952; 95% CI, 1.43–44.10), puerperal infection (aOR, 6.864; 95% CI, 1.95–24.22), neonatal mild asphyxia (aOR, 4.339; 95% CI, 1.53–12.32), severe asphyxia (aOR, 18.439; 95% CI, 1.54–220.95), and admission to a neonatal intensive care unit (aOR, 2.825; 95% CI, 1.54–5.17) compared with the reference group (aged 25–29 years).ConclusionsMaternal age between 18 and 24 years or advanced maternal age at first cesarean was an independent risk factor for adverse maternal outcomes with the second cesarean. Advanced maternal age at the first cesarean specifically increased adverse neonatal outcomes with the second. Therefore, decisions as to whether to perform a first cesarean at a young or advanced maternal age must be critically evaluated.

1071 Uterine scars and risk of placenta accreta: is a prior myomectomy equivalent to a C-section?

To determine if history of prior myomectomy in those with prior CS increases the risk of placenta accreta spectrum (PAS) disorders. A retrospective cohort study of patients who delivered at a tertiary academic center from 2012-2019 and had a sonographic evaluation of the placenta during their pregnancy at a single ultrasound unit. Demographic, clinical history, sonographic results, and pathology information were collected. Women with a history of C-section and myomectomy were compared based on their number of prior C-sections to those without myomectomy. Analysis was done using Mann-Whitney U test and Chi-square as appropriate. All p-values were considered statistically significant if p <0.05. We identified 585 women with a history of prior C-section (CS) or prior CS with Myomectomy. Of 44 patients in the latter group, 39 (88.6%) had only one prior CS. The baseline characteristics of both groups were similar, except that women with Prior CS with Myomectomy were older (Table 1). The five patients with histologically-confirmed PAS and prior CS with Myomectomy all had one prior CS. Of 33 cases of PAS in the CS only group, 15 (45.4%) occurred in those with multiple prior CS. The rate of PAS in those with one prior CS with Myomectomy was higher compared to those with one prior CS only (12.8% vs. 4.6%; p=0.03), and comparable to those with multiple prior CS (10.3% vs. 12.8%; p=0.65). Of the 33 cases with PAS and CS only, 28 (84.8%) had placenta previa, compared to only 2 of 5 (40%) with PAS in the CS with Myomectomy group (p=.05). The rate of PAS in women with a history of 1 CS and myomectomy was higher compared to those with 1 CS alone, and more comparable to those with multiple prior CS. This suggests an incremental risk associated with myomectomy. As there were too few women with multiple CS with Myomectomy, the incremental risk associated with myomectomy in these women will require larger studies. PAS appears more likely to happen in the absence of placenta previa in those with prior myomectomy.

Placenta Accreta Spectrum Among Women With Twin Gestations.

To assess whether placenta accreta spectrum occurs more frequently among women with twin gestations compared with singleton gestations. All live births in California from 2016 to 2017 were identified from previously linked records of birth certificates and birth hospitalization discharges. The primary outcome was placenta accreta spectrum (which includes placenta accreta, increta, and percreta), identified using International Classification of Diseases, Tenth Revision, Clinical Modification codes (O43.2x) for placenta accreta, increta, and percreta. We analyzed the association between twin gestation and placenta accreta spectrum by using multivariable logistic regression and assessed whether our findings were replicated by using a previously validated International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)-based approach. Among 918,452 live births, 1,126 were diagnosed with placenta accreta spectrum. The prevalence of placenta accreta spectrum was 11.8 per 10,000 among singleton pregnancies and 41.6 per 10,000 among twin pregnancies. In the unadjusted regression analysis, twin pregnancy was associated with higher relative risk of placenta accreta spectrum (RR 3.41, 95% CI 2.57-4.52). After adjusting the regression model for maternal age, previous cesarean birth, and sociodemographic factors, the association held with higher relative risk of placenta accreta spectrum (aRR 2.96, 95% CI 2.23-3.93). Women with twin compared with singleton gestations with placenta accreta spectrum were less likely to have placenta previa. When assessed using ICD-9-CM codes, placenta accreta spectrum was similarly more prevalent among twins than singletons, with an increase in the relative risk of placenta accreta spectrum (aRR 2.45, 95% CI 2.33-3.25). Twin gestation conferred an increased risk for placenta accreta spectrum independent of measured risk factors, which may contribute to increased maternal morbidity in twin gestation compared with singleton gestation. Clinicians should be aware of the increased risk for placenta accreta spectrum in twin gestation and should consider it during ultrasonographic screening.

OC08.02: Outcomes of pregnancies at high risk for placenta accreta spectrum following negative diagnostic imaging

OC08.02: Outcomes of pregnancies at high risk for placenta accreta spectrum following negative diagnostic imaging

Placenta Accreta Spectrum Without Placenta Previa

To evaluate placenta accreta spectrum with and without placenta previa with regard to risk factors, antepartum diagnosis, and maternal morbidity. We conducted a retrospective cohort study of pathology-confirmed placenta accreta spectrum deliveries with hysterectomy from two U.S. referral centers from January 2010-June 2019. Maternal, pregnancy, and delivery characteristics were compared among placenta accreta spectrum cases with (previa PAS group) and without (nonprevia PAS group) placenta previa. Surgical outcomes and a composite of severe maternal morbidities were evaluated, including eight or more blood cell units transfused, reoperation, pulmonary edema, acute kidney injury, thromboembolism, or death. Logistic regression was used with all analyses controlled for delivery location. Of 351 deliveries, 106 (30%) had no placenta previa at delivery. When compared with the previa group, nonprevia placenta accreta spectrum was less likely to be identified antepartum (38%, 95% CI 28-48% vs 87%, 82-91%), less likely to receive care from a multidisciplinary team (41%, 31-51% vs 86%, 81-90%), and less likely to have invasive placenta increta or percreta (51% 41-61% vs 80%, 74-84%). The nonprevia group had more operative hysteroscopy (24%, 16-33% vs 6%, 3-9%) or in vitro fertilization (31%, 22-41% vs 9%, 6-13%) and was less likely to have had a prior cesarean delivery (64%, 54-73% vs 93%, 89-96%) compared with the previa group, though the majority in each group had a prior cesarean delivery. Rates of severe maternal morbidity were similar in the two groups, at 19% (nonprevia) and 20% (previa), even after controlling for confounders (adjusted odds ratio for the nonprevia group 0.59, 95% CI 0.30-1.17). Placenta accreta spectrum without previa is less likely to be diagnosed antepartum, potentially missing the opportunity for multidisciplinary team management. Despite the absence of placenta previa and less placental invasion, severe maternal morbidity at delivery was not lower. Broader recognition of patients at risk for placenta accreta spectrum may improve early clinical diagnosis and patient outcomes.

Association Between Myomectomy and Placenta Accreta Spectrum

Study Objective To examine the relationship between prior myomectomy and placenta accreta spectrum (PAS). Design A retrospective chart review of all laparoscopic and abdominal myomectomies performed between 2014 - 2016. Obstetrical outcomes following surgery were collected through April 2019. Setting An academic hospital with a comprehensive fibroid treatment center and a multidisciplinary treatment team dedicated to the management of placenta accreta. Patients or Participants All patients who underwent a laparoscopic myomectomy (standard and robotic-assisted) or abdominal myomectomy between 2014 - 2016. Interventions Demographics, pelvic imaging, intraoperative findings, fibroid burden on final pathology, and future mode of delivery recommendations were collected for each procedure. Subsequent obstetrical outcomes including clinical pregnancy, antepartum imaging suspicious for PAS, mode of delivery, clinical diagnosis of PAS, and pathologic PAS were collected for all patients. Measurements and Main Results Of 315 patients who underwent myomectomy between 2014 - 2016, 43 patients subsequently became pregnant, resulting in 23 deliveries (7.3%). 16 of 20 patients underwent a cesarean delivery due to history of a prior myomectomy, 13 of which had a documented endometrial cavity entry at time of myomectomy. There were three cases of clinical PAS at time of delivery, all associated with a prior abdominal myomectomy. Two cases had PAS confirmed on final pathology. Two cases were associated with possible intrauterine synechiae identified during a uterine cavity evaluation following myomectomy, prior to conception. Only one case had antepartum imaging concerning for PAS. There were no cases of PAS amongst patients who had undergone a laparoscopic myomectomy. Conclusion PAS was associated with prior abdominal but not laparoscopic myomectomy. The subsequent development of intrauterine synechiae following abdominal myomectomy may be an identifiable finding during postoperative uterine cavity evaluation. This finding may help stratify the risk of PAS following myomectomy prior to conception, and better guide preoperative risk counseling prior to cesarean delivery.

MRI of the Placenta Accreta Spectrum (PAS) Disorder: Radiomics Analysis Correlates With Surgical and Pathological Outcome.

Placenta accreta spectrum (PAS) in women with previous cesarean delivery has become increasingly prevalent. Depending on the severity, patient management may involve cesarean hysterectomy. To investigate textural analyses as the radiomics in MRI of the placenta in predicting the PAS requiring cesarean hysterectomy in a high-risk population. Retrospective. Sixty-two women with prior cesarean delivery referred for MRI because of sonographic suspicion for PAS. 1.5T with T1 W, T2 W, and diffusion-weighted imaging (DWI). Two reviewers independently evaluated MR images based on five established PAS variables. Placental regions of interest (ROIs) were generated on T2 W, DWI, and an apparent diffusion coefficient (ADC) map, based on definitions of areas of placenta in proximity to and remote from previous surgical incision sites. Reader agreement was assessed by simple kappa and prevalence adjusted bias adjusted kappa (PABAK). T-tests and chi-square analyses between the primary outcome (hysterectomy vs. no hysterectomy) were performed. Thirteen Haralick texture features calculated from gray-level co-occurrence matrixes were extracted from manually drawn placental ROIs within each of three MR acquisitions. Univariate and multivariable logistic regression were used to assess the association with cesarean hysterectomy. Of 62 pregnancies at risk for PAS, 40 required cesarean hysterectomy (65%), with excellent correlation between need for hysterectomy and pathology confirmation of PAS in the hysterectomy specimen [κ = 0.82 (0.62, 1)]. Reader agreement was fair to moderate. Of the 13 Haralick variables within each of three acquisition groups, significant differences (P < 0.05) were seen in 22 of 39 parameters comparing placental ROIs in proximity to incision scar(s) to those ROIs remote from scar. A stepwise selection algorithm indicated that the combination of T2 W Fcm.sum.var , ADC Fcm.diff.entr , and DWI Fcm.energy gave the highest leave-one-out-AUC of 0.80 (0.68, 0.91). Assessment of PAS severity is subjective and dependent on radiologist expertise. We identified textural features on placental MR images in the region of the prior uterine scar that differentiated pregnancies requiring cesarean hysterectomy based on clinical suspicion of PAS from those that did not, suggesting predictive capabilities of these objective radiomics features. 3 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2020;51:936-946.

Effect of Trial of Labor before Cesarean and Risk of Subsequent Placenta Accreta Spectrum Disorders.

This study aimed to examine whether labor before cesarean affects the risk of placenta accreta spectrum (PAS) disorders in a subsequent pregnancy. This is a secondary analysis of the Cesarean Registry, a prospective cohort study of women undergoing cesarean between 1999 and 2002. Women with one prior cesarean with known indications, which were categorized as likely associated with labor (labored cesarean) versus likely not associated with labor (unlabored cesarean), were included. Primary outcome was PAS disorder. Of 34,224 women, 60% had a "labored cesarean" and 40% had an "unlabored cesarean." Women with prior unlabored cesarean were more likely to have subsequent PAS disorder compared with women with a prior labored cesarean after adjusting for confounders (0.28 vs. 0.13%; adjusted odds ratio: 2.03; 95% confidence interval: 1.22-3.38). Prior unlabored cesarean is associated with an increased risk of PAS disorders in a subsequent pregnancy. This association may aid in risk stratification in women with suspected PAS disorders and help counsel about risks associated with cesarean on maternal request.