Trophectoderm grade is associated with the risk of placenta previa in frozen-thawed single-blastocyst transfer cycles.

STUDY QUESTION: Do obstetric and perinatal complications vary according to different blastocyst developmental parameters after frozen-thawed single-blastocyst transfer (SBT) cycles? SUMMARY ANSWER: Pregnancies following the transfer of a blastocyst with a grade C trophectoderm (TE) were associated with an increased risk of placenta previa compared to those with a blastocyst of grade A TE. WHAT IS KNOWN ALREADY: Existing studies investigating the effect of blastocyst morphology grades on birth outcomes have mostly focused on fetal growth and have produced conflicting results, while the risk of obstetric complications has rarely been reported. Additionally, growing evidence has suggested that the appearance of TE cells could serve as the most important parameter for predicting implantation and live birth. Given that the TE ultimately develops into the placenta, it is plausible that this independent predictor may also impact placentation. STUDY DESIGN, SIZE, DURATION: This retrospective cohort study at a tertiary-care academic medical center included 6018 singleton deliveries after frozen-thawed SBT cycles between January 2017 and December 2021. PARTICIPANTS/MATERIALS, SETTING, METHODS: Singleton pregnancies were grouped into two groups according to blastocyst developmental stage (Days 5 and 6), four groups according to embryo expansion (Stages 3, 4, 5, and 6), three groups according to inner cell mass (ICM) quality (A, B, and C), and three groups according to TE quality (A, B, and C). The main outcomes included pregnancy-induced hypertension, preeclampsia, gestational diabetes mellitus, preterm premature rupture of membrane, placenta previa, placental abruption, placenta accreta, postpartum hemorrhage, preterm birth, low birth weight, small for gestational age, and birth defects. Multivariate logistic regressions were performed to evaluate the effect of blastocyst developmental stage, embryo expansion stage, ICM grade, and TE grade on measured outcomes adjusting for potential confounders. MAIN RESULTS AND THE ROLE OF CHANCE: No association was found between blastocyst developmental stage and obstetric or perinatal outcomes both before and after adjusting for potential confounders, and similar results were found with regard to embryo expansion stage and ICM grade. Meanwhile, the incidence of placenta previa derived from a blastocyst with TE of grade C was higher compared with those derived from a blastocyst with TE of grade A (1.7%, 2.4%, and 4.0% for A, B, and C, respectively, P = 0.001 for all comparisons). After adjusting for potential covariates, TE grade C blastocysts had 2.81 times the likelihood of resulting in placenta previa compared to TE grade A blastocysts (adjusted odds ratio 2.81, 95% CI 1.11-7.09). No statistically significant differences were detected between any other measured outcomes and TE grades both before or after adjustment. LIMITATIONS, REASONS FOR CAUTION: The study is limited by its retrospective, single-center design. Additionally, although the sample size was relatively large for the study group, the sample size for certain subgroups was relatively small and lacked adequate power, particularly the ICM grade C group. Therefore, these results should be interpreted with caution. WIDER IMPLICATIONS OF THE FINDINGS: The study extends our knowledge of the potential downstream effect of TE grade on placental abnormalities. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the National Key Research and Development Program of China (2023YFC2705500, 2023YFC2705501, 2023YFC2705505, 2019YFA0802604); National Natural Science Foundation of China (82130046, 82320108009, 82371660, 32300710); Shanghai leading talent program, Innovative research team of high-level local universities in Shanghai (SHSMU-ZLCX20210201, SHSMU-ZLCX20210200, SHSMU-ZLCX20180401), Shanghai Jiaotong University School of Medicine Affiliated Renji Hospital Clinical Research Innovation Cultivation Fund Program (RJPY-DZX-003), Science and Technology Commission of Shanghai Municipality (23Y11901400), Shanghai's Top Priority Research Center Construction Project (2023ZZ02002), and Three-Year Action Plan for Strengthening the Construction of the Public Health System in Shanghai (GWVI-11.1-36). The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Evaluation of maternal serum VEGF, TNF-alpha, IL-4, and IL-10 levels in differentiating placenta accreta spectrum from isolated placenta previa.

OBJECTIVE: Our study aimed to differentiate patients with placenta accreta spectrum (PAS) from those with placenta previa (PP) using maternal serum levels of vascular endothelial growth factor (VEGF), tumor necrosis factor-alpha (TNF-alpha), interleukin-4 (IL-4), and IL-10. METHODS: The case group consisted of 77 patients with placenta previa, and the control group consisted of 90 non-previa pregnant women. Of the pregnant women in the case group, 40 were diagnosed with PAS in addition to placenta previa and 37 had placenta previa with no invasion. The maternal serum VEGF, TNF-alpha, IL-4, and IL-10 levels were compared between the case and control groups. Then the success of these markers in differentiating between PP and PAS was evaluated. RESULTS: We found the VEGF, TNF-alpha, and IL-4 levels to be higher and the IL-10 level to be lower in the case group compared to the control group (p < 0.001). We observed a statistically significantly lower IL-10 level in the patients with PAS than those with PP (p = 0.029). In the receiver operating characteristic analysis, the optimal cut-off of IL-10 in the detection of PAS was 0.42 ng/mL). In multivariate analysis, the risk of PAS was significant for IL-10 (odds ratio (OR) 0.45, 95 % confidence interval (CI) 0.25-0.79, p = 0.006) and previous cesarean section (OR 2.50, 95 % Cl 1.34-4.66, p = 0.004). The model's diagnostic sensitivity and specificity, including previous cesarean section, preoperative hemoglobin (Hb), TNF-alpha, and IL-10 were 75 % and 72.9 %, respectively. CONCLUSION: The study showed that the IL-10 level was lower in patients with PAS than in those with PP. A statistical model combining risk factors including previous cesarean section, preoperative Hb, TNF-alpha, and IL-10 may improve clinical diagnosis of PAS in placenta previa cases. Cytokines may be used as additional biomarkers to the clinical risk factors in the diagnosis of PAS.

Real-time ultrasound demonstration of uterine isthmus contractions during pregnancy.

BACKGROUND: Asymptomatic isthmic contractions are a frequent physiological phenomenon in pregnancy, sometimes triggered by bladder voiding. They can interfere with proper cervical length assessment and may lead to false images of placenta previa. However, there is limited research on the prevalence and characteristics of these contractions. OBJECTIVE: This study aimed to determine the prevalence and characteristics of isthmic contractions after bladder voiding in the second trimester of pregnancy, to evaluate their effect on cervical length assessment, and to propose a new method for the objective assessment of the presence and intensity of isthmic contractions. STUDY DESIGN: In this prospective observational study, long videos of the uterine cervix were recorded in 30 singleton pregnancies during the second trimester of pregnancy after bladder voiding. Isthmic length and cervicoisthmic length changes were assessed over time. The isthmic length was measured using a new approach, which involved calculating the distance from the base of the cervix to the internal os, including the isthmus. RESULTS: Isthmic contractions were observed in 43% of pregnant women (95% confidence interval, 26%-62%) after bladder voiding. The median time for complete isthmus relaxation was 19.7 minutes (95% confidence interval, 15.0 to not available). No substantial differences in maternal characteristics were found between individuals with and without contractions. The proposed method for measuring isthmic length provided an objective assessment of the presence and intensity of isthmic contractions. A cutoff of 18 mm in isthmic length allowed for the distinction of pregnant women presenting a contraction. In addition, the study identified a characteristic undulatory pattern in the relaxation of the isthmus in half of the cases with contractions. CONCLUSION: Isthmic contractions are a common occurrence after bladder voiding in the second trimester of pregnancy and may interfere with proper cervical length assessment. We recommend performing cervical assessment at least 20 minutes after bladder voiding to reduce the risk of bias in cervical length measurement and to avoid false images of placenta previa. The new method for measuring isthmic length provides an objective way to assess the presence and intensity of isthmic contractions. Further research is needed to understand the role of isthmic contractions in the physiology of pregnancy and birth.

Development and validation of MRI-based scoring models for predicting placental invasiveness in high-risk women for placenta accreta spectrum.

OBJECTIVES: To develop and validate MRI-based scoring models for predicting placenta accreta spectrum (PAS) invasiveness. MATERIALS AND METHODS: This retrospective study comprised a derivation cohort and a validation cohort. The derivation cohort came from a systematic review of published studies evaluating the diagnostic performance of MRI signs for PAS and/or placenta percreta in high-risk women. The significant signs were identified and used to develop prediction models for PAS and placenta percreta. Between 2016 and 2021, consecutive high-risk pregnant women for PAS who underwent placental MRI constituted the validation cohort. Two radiologists independently evaluated the MRI signs. The reference standard was intraoperative and pathologic findings. The predictive ability of MRI-based models was evaluated using the area under the curve (AUC). RESULTS: The derivation cohort included 26 studies involving 2568 women and the validation cohort consisted of 294 women with PAS diagnosed in 258 women (88%). Quantitative meta-analysis revealed that T2-dark bands, placental/uterine bulge, loss of T2 hypointense interface, bladder wall interruption, placental heterogeneity, and abnormal intraplacental vascularity were associated with both PAS and placenta percreta, and myometrial thinning and focal exophytic mass were exclusively associated with PAS. The PAS model was validated with an AUC of 0.90 (95% CI: 0.86, 0.93) for predicting PAS and 0.85 (95% CI: 0.79, 0.90) for adverse peripartum outcome; the placenta percreta model showed an AUC of 0.92 (95% CI: 0.86, 0.98) for predicting placenta percreta. CONCLUSION: MRI-based scoring models established based on quantitative meta-analysis can accurately predict PAS, placenta percreta, and adverse peripartum outcome. CLINICAL RELEVANCE STATEMENT: These proposed MRI-based scoring models could help accurately predict PAS invasiveness and provide evidence-based risk stratification in the management of high-risk pregnant women for PAS. KEY POINTS: • Accurately identifying placenta accreta spectrum (PAS) and assessing its invasiveness depending solely on individual MRI signs remained challenging. • MRI-based scoring models, established through quantitative meta-analysis of multiple MRI signs, offered the potential to predict PAS invasiveness in high-risk pregnant women. • These MRI-based models allowed for evidence-based risk stratification in the management of pregnancies suspected of having PAS.

Determinants of emergency Cesarean delivery in pregnancies complicated by placenta previa with or without placenta accreta spectrum disorder: analysis of ADoPAD cohort.

OBJECTIVES: To investigate the rate and outcome of emergency Cesarean delivery (CD) in women with placenta previa with or without placenta accreta spectrum disorders (PAS) and to elucidate the diagnostic accuracy of ultrasound in predicting emergency CD. METHODS: This was a secondary analysis of a multicenter prospective study involving 16 referral hospitals in Italy (ADoPAD study). Inclusion criteria were women with placenta previa minor (< 20 mm from the internal cervical os) or placenta previa major (covering the os), aged ≥ 18 years, who underwent transabdominal and transvaginal ultrasound assessment at ≥ 26 + 0 weeks of gestation. The primary outcome was the occurrence of emergency CD, defined as the need for immediate surgical intervention performed for emergency maternal or fetal indication, including active labor, cumulative maternal bleeding > 500 mL, severe and persistent vaginal bleeding such that maternal hemodynamic stability could not be achieved or maintained, or category-III fetal heart rate tracing unresponsive to resuscitative measures. The primary outcome was reported separately in the population of women with placenta previa and no PAS confirmed after birth and in those with PAS. The secondary aim was to report on the strength of association and to test the diagnostic accuracy of ultrasound in predicting emergency CD. Univariate, multivariate and diagnostic accuracy analyses were used to analyze the data. RESULTS: A total of 450 women, including 97 women with placenta previa and PAS and 353 with placenta previa only, were analyzed. In women with placenta previa and PAS, emergency CD was required in 20.6% (95% CI, 14-30%), and 60.0% (12/20) delivered before 34 weeks of gestation. The mean gestational age at delivery was 32.3 ± 2.7 weeks in women undergoing emergency CD and 34.9 ± 1.8 weeks in those undergoing elective CD (P < 0.001). Women undergoing emergency CD had a higher median estimated blood loss (2500 (interquartile range (IQR), 1350-4500) vs 1100 (IQR, 625-2500) mL; P = 0.012), mean units of blood transfused (7.3 ± 8.8 vs 2.5 ± 3.4; P = 0.02) and more frequent placement of a mechanical balloon (50.0% vs 16.9%; P = 0.002) compared with those undergoing elective CD. On univariate analysis, the presence of interrupted retroplacental space, interrupted bladder line and placental lacunae was more common in women not experiencing emergency CD. No comprehensive multivariate analysis could be performed in this subgroup of women. Ultrasound signs of PAS, including presence of interrupted retroplacental space, interrupted bladder line and placental lacunae, were not predictive of emergency CD. In women with placenta previa but no PAS, emergency CD was required in 31.2% (95% CI, 26.6-36.2%), and 32.7% (36/110) delivered before 34 weeks of gestation. The mean gestational age at delivery was lower in women undergoing emergency CD compared with those undergoing elective CD (34.2 ± 2.9 vs 36.7 ± 1.6 weeks; P < 0.001). Pregnancies complicated by emergency CD were associated with a lower birth weight (2330 ± 620 vs 2800 ± 480 g; P < 0.001) and had a higher risk of need for blood transfusion (22.7% vs 10.7%; P = 0.003) compared with those who underwent elective CD. On multivariate analysis, only placental thickness (odds ratio (OR), 1.02 (95% CI, 1.00-1.03); P = 0.046) and cervical length < 25 mm (OR, 3.89 (95% CI, 1.33-11.33); P = 0.01) were associated with emergency CD. However, a short cervical length showed low diagnostic accuracy for predicting emergency CD in these women. CONCLUSION: Emergency CD occurred in about 20% of women with placenta previa and PAS and 30% of those with placenta previa only and was associated with worse maternal outcome compared with elective intervention. Prenatal ultrasound is not predictive of the risk of emergency CD in women with these disorders. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Evaluation of preoperative ultrasound signs associated with bladder injury during complex Cesarean delivery: case-control study.

OBJECTIVE: Intraoperative hemorrhage and peripartum hysterectomy are the main complications in patients presenting with a low-lying placenta or placenta previa undergoing repeat Cesarean delivery (CD). Patients with a high probability of placenta accreta spectrum (PAS) at birth also have a higher risk of intraoperative urologic injury. The aim of this study was to evaluate the ultrasound signs and intraoperative features associated with these injuries. METHODS: This was a retrospective case-control study of consecutive singleton pregnancies included in a prospective cohort of patients with a history of at least one prior CD and diagnosed prenatally with an anterior low-lying placenta or placenta previa at 32-36 weeks' gestation. All patients underwent investigational preoperative transabdominal and transvaginal ultrasound examination within 48 h prior to delivery. Ultrasound anomalies of uterine contour and uteroplacental vascularity, and gross anomalies of the lower uterine segment (LUS) and surrounding pelvic tissue at delivery, were recorded using a standardized protocol, which included evaluation of the extent of uterine contour anomalies. The diagnosis of PAS was established when one or more placental lobules could not be separated digitally from the uterine wall at delivery or during the gross examination of the hysterectomy or partial myometrial resection specimens, and was confirmed by histopathology. Data were compared between cases complicated by intraoperative bladder injury and controls from the same cohort matched at a 1:3 ratio by parity and the number of prior CDs using conditional logistic regression. RESULTS: There were 16 (9.4%) patients with an intraoperative bladder injury in a cohort of 170 managed by the same multidisciplinary team during the study period. There were no patients diagnosed with ureteric or bladder trigone damage. There were 14 (87.5%) patients with a bladder injury that had histopathologic evidence of PAS at birth, including 11 (68.8%) cases described on microscopic examination as placenta increta and three (18.8%) as placenta creta. There was a significant (P = 0.03) difference between cases and controls in the distribution of intraoperative LUS vascularity, whereby the higher the number of enlarged vessels, the higher the odds of bladder injury. Multivariable regression analysis revealed that both gestational age at delivery and LUS remodeling on transabdominal ultrasound were associated with bladder injury. A higher gestational age was associated with a lower risk of injury. A higher LUS remodeling grade on transabdominal ultrasound was associated with an increased risk of bladder injury. Patients with Grade-3 remodeling (involving > 50% of the LUS) had 9-times higher odds of a bladder injury compared to patients with Grade-1 remodeling (involving < 30% of the LUS). CONCLUSIONS: Preoperative ultrasound examination is useful in the evaluation of the risk of intraoperative bladder injury in patients with a history of prior CD presenting with a low-lying placenta or placenta previa. The larger the remodeling of the LUS on transabdominal ultrasound, the higher the risk of adverse urologic events. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Incidence, risk factors and maternal outcomes of unsuspected placenta accreta spectrum disorders: a retrospective cohort study.

BACKGROUND: To identify incidence and underlying risk factors for unsuspected placenta accreta spectrum (PAS) and compare the maternal outcomes between suspected and unsuspected cases in three large academic referral centers. METHODS: A retrospective cohort study was conducted in three university-based tertiary referral centers from Jan 1st, 2013, to Dec 31st, 2022. All cases of PAS confirmed by pathology were included in the study. Unsuspected PAS cases were diagnosed at the time of delivery, while suspected cases served as the control group. Potential risk factors were compared between the two groups. Multivariable regression model was also performed to identify risk factors. Maternal outcomes were also evaluated. RESULTS: A total of 339 pathology-confirmed PAS cases were included in the study out of 415,470 deliveries, of which 35.4% (n = 120) were unsuspected cases. Unsuspected PAS cases were 7.9 times more likely to have a history of intrauterine adhesions (adjusted odds ratio [aOR] 7.93; 95% confidence interval [CI] 2.35-26.81), 7.0 times more likely to have a history of clinically confirmed PAS (aOR, 6.99; 95% CI 2.85-17.18), 6.3 times more likely to have a posterior placenta (aOR, 6.30; 95% CI 3.48-11.40), and 3.4 times more likely to have a history of placenta previa (aOR, 3.41; 95% CI 1.18-9.82). On the other hand, cases with gravidity > 3, placenta previa, and/or a history of previous cesarean delivery were more likely to be diagnosed antenatally (aOR 0.40, 0.19, 0.36; 95% CI 0.22-0.74, 0.09-0.40, 0.19-0.70). Although the suspected PAS group had a higher proportion of invasive cases and abdominal and pelvic organ injuries (74.4% vs. 25.8%, p < 0.001; 6.8% vs. 1.7%, p = 0.037), the maternal outcomes were more favorable in the sPAS group, with a lower median volume of 24-hour blood loss and blood product transfusion (estimated blood loss in 24 h, 1000 [800-2000] vs. 2000 [1400-2400], p < 0.001; RBC unit transfusion, 0 [0-800] vs. 800 [600-1000], p < 0.001; fresh-frozen plasma transfusion, 0 [0-450] vs. 600 [400-800], p < 0.001). CONCLUSIONS: Our findings indicate that 35% of patients with PAS were unsuspected prior to delivery. Factors associated with PAS being unsuspected prior to delivery include a history of intrauterine adhesions, a history of clinically confirmed PAS, a posterior placenta, and a history of placenta previa. Additionally, gravidity > 3, a history of previous cesarean delivery, and placenta previa increase the likelihood of antenatal diagnosis.

Obstetric blood transfusion in placenta previa patients with prenatal anemia: a retrospective study.

BACKGROUND: The appropriate use of obstetric blood transfusion is crucial for patients with placenta previa and prenatal anemia. This retrospective study aims to explore the correlation between prenatal anemia and blood transfusion-related parameters in this population. METHODS: We retrieved the medical records of consecutive participants who were diagnosed with placenta previa and underwent cesarean section in our hospital. We compared the baseline demographics and clinical characteristics of patients with and without anemia. The correlation between prenatal anemia and obstetric blood transfusion-related parameters was evaluated using multivariate regression analysis. RESULTS: A total of 749 patients were enrolled, with a mean prenatal hemoglobin level of 10.87 ± 1.37 g/dL. Among them, 54.87% (391/749) were diagnosed with anemia. The rate of obstetric blood transfusion was significantly higher in the anemia group (79.54%) compared to the normal group (44.41%). The median allogeneic red blood cell transfusion volume in the anemia group was 4.00 U (IQR 2.00-6.00), while in the normal group, it was 0.00 U (IQR 0.00-4.00). The prenatal hemoglobin levels had a non-linear relationship with intraoperative allogeneic blood transfusion rate, massive blood transfusion rate, red blood cell transfusion units, and fresh plasma transfusion volume in patients with placenta previa, with a threshold of 12 g/dL. CONCLUSIONS: Our findings suggest that prenatal anemia is associated with a higher rate of blood transfusion-related parameters in women with placenta previa when the hemoglobin level is < 12 g/dL. These results highlight the importance of promoting prenatal care in placenta previa patients with a high requirement for blood transfusion.

The relationship between cervical length and area measurements evaluated by MRI and the amount of hemorrhage in PAS cases.

BACKGROUND: Placenta accreta spectrum often leads to massive hemorrhage and even maternal shock and death. This study aims to identify whether cervical length and cervical area measured by magnetic resonance imaging correlate with massive hemorrhage in patients with placenta accreta spectrum. METHODS: The study was conducted at our hospital, and 158 placenta previa patients with placenta accreta spectrum underwent preoperative magnetic resonance imaging examination were included. The cervical length and cervical area were measured and evaluated their ability to identify massive hemorrhage in patients with placenta accreta spectrum. RESULTS: The cervical length and area in patients with massive hemorrhage were both significantly smaller than those in patients without massive hemorrhage. The results of multivariate analysis show that cervical length and cervical area were significantly associated with massive hemorrhage. In all patients, a negative linear was found between cervical length and amount of blood loss (r =-0.613), and between cervical area and amount of blood loss (r =-0.629). Combined with cervical length and cervical area, the sensitivity, specificity, and the area under the curve for the predictive massive hemorrhage were 88.618%, 90.209%, and 0.890, respectively. CONCLUSION: The cervical length and area might be used to recognize massive hemorrhage in placenta previa patients with placenta accreta spectrum.

Association between endometriosis and perinatal complications: a case-control study.

BACKGROUND: Recently, a history of endometriosis has been reported to be associated with several perinatal complications. However, it is unknown whether pre-pregnancy treatment for endometriosis reduces perinatal complications. In this study, we aimed to clarify the association between endometriosis and perinatal complications and investigate whether there is a significant difference in the incidence of placenta previa depending on the degree of surgical completion of endometriosis before pregnancy. METHODS: This case-control study included 2781 deliveries at the Hirosaki University Hospital between January 2008 and December 2019. The deliveries were divided into a case group with a history of endometriosis (n = 133) and a control group without endometriosis (n = 2648). Perinatal outcomes and complications were compared between the case and control groups using a t-test and Fisher's exact test. Multiple logistic regression models were used to identify the risk factors for placenta previa. Additionally, we examined whether the degree of surgical completion of endometriosis before pregnancy was associated with the risk of placenta previa. RESULTS: Patients with a history of endometriosis had a significantly higher risk of placenta previa (crude odds ratio, 2.66; 95% confidence interval, 1.37‒4.83). Multiple logistic regression analysis showed that a history of endometriosis was a significant risk factor for placenta previa (adjusted odds ratio, 2.30; 95% confidence interval, 1.22‒4.32). In addition, among patients with revised American Society for Reproductive Medicine stage III-IV endometriosis, the incidence of placenta previa was significantly lower in patients who underwent complete surgery (3/51 patients, 5.9%) than in those who did not (3/9 patients, 33.3%) (p = 0.038). CONCLUSIONS: A history of endometriosis is an independent risk factor for placenta previa. Given the limitations of this study, further research is needed to determine the impact of endometriosis surgery on perinatal complications.

Cesarean hysterectomy in pregnancies complicated with placenta previa accreta: a retrospective hospital-based study.

BACKGROUND: Placenta previa accreta (PPA) is a severe obstetric condition that can cause massive postpartum hemorrhage and transfusion. Cesarean hysterectomy is necessary in some severe cases of PPA to stop the life-threatening bleeding, but cesarean hysterectomy can be associated with significant surgical blood loss and major complications. The current study is conducted to investigate the potential risk factors of excessive blood loss during cesarean hysterectomy in women with PPA. METHODS: This is a retrospective study including singleton pregnancies after 28 weeks of gestation in women with placenta previa and pathologically confirmed placenta accreta spectrum who received hysterectomy during cesarean sections. A total of 199 women from January 2012 to August 2023 were included in this study and were divided into Group 1 (estimated surgical blood loss (EBL) ≤ 3500 mL, n = 103) and Group 2 (EBL > 3500 mL, n = 96). The primary outcome was defined as an EBL over 3500 mL. Baseline characteristics and surgical outcomes were compared between the two groups. A multivariate logistic regression model was applied to find potential risk factors of the primary outcome. RESULTS: Massive surgical blood loss was prevalent in our study group, with a median EBL of 3500 mL. The multivariate logistic analysis showed that emergency surgery (OR 2.18, 95% CI 1.08-4.41, p = 0.029), cervical invasion of the placenta (OR 2.70, 95% CI 1.43-5.10, p = 0.002), and intraoperative bladder injury (OR 5.18, 95% CI 2.02-13.28, p = 0.001) were all associated with the primary outcome. Bilateral internal iliac arteries balloon occlusion (OR 0.57, 95% CI 0.34-0.97) and abdominal aortic balloon occlusion (OR 0.33, 95% CI 0.19-0.56) were negatively associated with the primary outcome. CONCLUSIONS: Emergency surgery, cervical invasion of the placenta, and intraoperative bladder injury were potential risk factors for additional EBL during cesarean hysterectomy in women with PPA. Future prospective studies are needed to confirm the effect of intra-arterial balloon occlusion in cesarean hysterectomy of PPA.

Risk factors of severe postpartum hemorrhage in pregnant women with placenta previa or low-lying placenta: a retrospective cohort study.

BACKGROUND: The severe postpartum hemorrhage (SPPH) leads to dangerous maternal conditions, and its rate is still increasing and the trend in related risk factors is changing. Placenta-related problems remain the high-risk factor for SPPH. The object is to investigate the prevalence and the risk factors of the severe postpartum hemorrhage in pregnant women with placenta previa or low-lying placenta. METHOD: A retrospective analysis of pregnant women with placenta previa or low-lying placenta after 28 weeks gestation from May 2018 to May 2023 in the Peking Union Medical College Hospital was conducted. The primary outcome was severe postpartum hemorrhage defined as blood loss ≥ 1000 mL within 24 h of childbirth, or with signs or symptoms of low blood volume requiring transfusion of ≥ 4U of red blood cells. Univariate and multivariate logistic regression were used to identify potential risk factors of severe postpartum hemorrhage and receiver operating curve to evaluate the prediction performance. RESULTS: Of the 14,964 women, 201 met the inclusive criteria. SPPH rate was 1.3% overall and 18.9% in women with placenta previa or low-lying placenta. Weight (aOR = 0.93, 95%CI 0.87-0.99), increta or percreta placenta (aOR = 7.93, 95%CI 2.53-24.77) were the risk factors. The area under the ROC curve was 0.69(95%CI 0.59-0.80) for increta or percreta placenta alone, and 0.72(95%CI 0.62-0.82) for the combination of times of cesarean sections and anterior placenta. CONCLUSIONS: Placenta accreta spectrum was the key independent risk factor of SPPH in women with placenta previa or low-lying placenta. Antenatal risk assessment of SPPH in these population is highly desirable and optimal intervention could be planned.

Placental volume as a novel sign for identifying placenta accreta spectrum in pregnancies with complete placenta previa.

BACKGROUND: Placenta accreta spectrum (PAS) carries an increased risk of maternal-fetal mortality and morbidity, and magnetic resonance imaging (MRI) features for PAS have been used for preoperative identification. This study aims to investigate the role of placental volume evaluated by MRI in identifying PAS in pregnant women with complete placenta previa. METHODS: Totally 163 cases of complete placenta previa pregnant women with a history of cesarean section underwent MRI for suspected PAS were included. We categorized the patients into two groups according to the presence or absence of PAS, and the maternal-fetal perinatal outcomes and placental volume analyzed by 3D Slice software were compared. RESULTS: There were significantly more gravidity, parity, and number of previous cesarean delivery in the PAS group (P < 0.05). Significant differences were also found between the two groups with respect to the following baseline characteristics: gestational age at delivery, intraoperative blood loss, blood transfusion, and neonatal birth weight (P < 0.05). Of 163 women in the study, 7 (4.294%) required cesarean hysterectomy for high-grade PAS or pernicious bleeding during cesarean section, and PAS was confirmed with histologic confirmation in 6 (85.714%) cases. The placental volume in PAS group was greater than that in the non-PAS group (P < 0.05). With a threshold of more than 887 cm3, the sensitivity and specificity in identifying PAS were 85.531% and 83.907% respectively, with AUC 0.908 (95% CI: 0.853-0.948). CONCLUSIONS: Placental volume may be a promising indicator of PAS in complete placenta previa patients with a history of cesarean section.

Nomogram based on clinical characteristics and ultrasound indicators for predicting severe postpartum hemorrhage in patients with anterior placenta previa combined with previous cesarean section: a retrospective case-control study.

BACKGROUND: Placental accreta spectrum disorders (PAS) are a high-risk group for severe postpartum hemorrhage (SPPH), with the incidence of PAS increasing annually. Given that cesarean section and anterior placenta previa are the primary risk factors for PAS, therefore, our study aims to investigate the predictive value of clinical characteristics and ultrasound indicators for SPPH in patients with anterior placenta previa combined with previous cesarean section, providing a theoretical basis for early prediction of SPPH. METHODS: A total of 450 patients with anterior placenta previa combined with previous cesarean section were retrospectively analyzed at Shengjing Hospital affiliated with China Medical University between January 2018 and March 2022. Clinical data and ultrasound indicators were collected. Patients were categorized into SPPH (blood loss >2000mL, 182 cases) and non-SPPH (blood loss ≤ 2000mL, 268 cases) groups based on the blood loss within 24 h postpartum. The population was randomly divided into training and validation cohorts at a 7:3 ratio. LASSO and multifactorial logistic regression analyses were utilized to identify independent risk factors for SPPH. Accordingly, a nomogram prediction model was constructed, the predictive performance was assessed using receiver operating characteristic (ROC) curves, calibration curves and decision curve analysis (DCA). RESULTS: Among the 450 patients, 182 experienced SPPH (incidence rate, 40.44%). Preoperative systemic immune-inflammatory index, preoperative D-dimer level, preoperative placenta accreta spectrum ultrasound scoring system (PASUSS) score, and one-step-conservative surgery were identified as independent risk factors for SPPH in patients with anterior placenta previa combined with previous cesarean section. A nomogram was constructed based on these factors. The areas under the ROC curves for the training and validation cohorts were 0.844 (95%CI: 0.801-0.888) and 0.863 (95%CI: 0.803-0.923), respectively. Calibration curves and DCA indicated that this nomogram demonstrated good predictive accuracy. CONCLUSIONS: This nomogram presents an effective and convenient prediction model for identifying SPPH in patients with anterior placenta previa combined with previous cesarean section. It can guide surgical planning and improve prognosis.

Transabdominal and transvaginal ultrasound findings help to guide the clinical management of placenta accreta spectrum cases.

INTRODUCTION: The clinical management of placenta accreta spectrum (PAS) depends on placental topography and vascular involvement. Our aim was to determine whether transabdominal and transvaginal ultrasound signs can predict PAS management. MATERIAL AND METHODS: We conducted a retrospective cohort study of consecutive prenatally suspected PAS cases in a single tertiary-care PAS center between January 2021 and July 2022. When PAS was confirmed during surgery, abdominal and transvaginal ultrasound scans were analyzed in relation to PAS management. The preferred surgical approach of PAS was one-step conservative surgery (OSCS). Massive blood loss and PAS topography in the lower bladder trigone necessitated cesarean hysterectomy. Transvaginal ultrasound-diagnosed intracervical hypervascularity was split into three categories based on their quantity. Anatomically, the internal cervical os is located at the level of the bladder trigone and was used as landmark for upper and lower bladder trigone PAS. RESULTS: Ninety-one women underwent OSCS and 35 women underwent cesarean hysterectomy (total 126 women with PAS). Abdominal and transvaginal ultrasound features differed significantly between women that underwent OSCS and cesarean hysterectomy: decreased myometrial thickness (<1 mm), 82.4% vs. 100%, p = 0.006; placental bulge, 51.6% vs. 94.3%, p < 0.001; bladder wall interruption, 62.6% vs. 97.1%, p < 0.001; abnormal placental lacunae, 75.8% vs. 100%, p < 0.001; hypervascularity (large lacunae feeding vessels, 57.8% vs. 94.6%, p < 0.001; parametrial hypervascularity, 15.4% vs. 60%, p < 0.001; the rail sign, 6.6% vs. 28.6%, p = 0.003; three-dimensional Doppler intra-placental hypervascularity, 81.3% vs. 100%, p < 0.001; intracervical hypervascularity 60.4% vs. 94.3%, p < 0.001); and cervical length 2.5 ± 0.94 vs. 2.2 ± 0.73, p = 0.038. Other ultrasound signs were not significantly different. The results of multivariable logistic regression showed placental bulge (odds ratio [OR] 9.3; 95% CI 1.9-44.3; p = 0.005), parametrial hypervascularity (OR 4.1; 95% CI 1.541-11.085; p = 0.005), and intracervical hypervascularity (OR 9.2; 95% CI 1.905-44.056; p = 0.006) were weak predictors of OSCS. Intracervical hypervascularity Grade 1 (vascularity <50% of cervical tissue) was more present in OSCS than higher gradings two and three (91% vs. 27.6% vs. 14.3%; p < 0.001). CONCLUSIONS: Cesarean hysterectomy is associated with the PAS signs of placental bulge and Grade 2 and 3 intracervical hypervascularity. OSCS is associated with intracervical hypervascularity Grade 1 on transvaginal ultrasound. Prospective validation is required to formulate predictors for PAS management.

Pregnancy outcomes of monochorionic diamniotic and dichorionic diamniotic twin pregnancies conceived by assisted reproductive technology and conceived naturally: a study based on chorionic comparison.

OBJECTIVE: To evaluate monochorionic diamniotic (MCDA) and dichorionic diamniotic (DCDA) twin pregnancies conceived by assisted reproductive technology (ART) and conceived naturally. METHODS: We retrospectively analyzed the data on twin pregnancies conceived by ART from January 2015 to January 2022,and compared pregnancy outcomes of MCDA and DCDA twins conceived by ART with those of MCDA and DCDA twins conceived naturally, pregnancy outcomes between MCDA and DCDA twins conceived by ART, and pregnancy outcomes of DCT and TCT pregnancies reduced to DCDA pregnancies with those of DCDA pregnancies conceived naturally. RESULT: MCDA pregnancies conceived by ART accounted for 4.21% of the total pregnancies conceived by ART and 43.81% of the total MCDA pregnancies. DCDA pregnancies conceived by ART accounted for 95.79% of the total pregnancies conceived by ART and 93.26% of the total DCDA pregnancies. Women with MCDA pregnancies conceived by ART had a higher premature delivery rate, lower neonatal weights, a higher placenta previa rate, and a lower twin survival rate than those with MCDA pregnancies conceived naturally (all p < 0.05). Women with DCDA pregnancies conceived naturally had lower rates of preterm birth, higher neonatal weights, and higher twin survival rates than women with DCDA pregnancies conceived by ART and those with DCT and TCT pregnancies reduced to DCDA pregnancies (all p < 0.05). CONCLUSION: Our study confirms that the pregnancy outcomes of MCDA pregnancies conceived by ART are worse than those of MCDA pregnancies conceived naturally. Similarly, the pregnancy outcomes of naturally-conceived DCDA pregnancies are better than those of DCDA pregnancies conceived by ART and DCT and TCT pregnancies reduced to DCDA pregnancies.

The influence of uterine fibroids on adverse outcomes in pregnant women: a meta-analysis.

OBJECTIVE: The objective of the meta-analysis was to determine the influence of uterine fibroids on adverse outcomes, with specific emphasis on multiple or large (≥ 5 cm in diameter) fibroids. MATERIALS AND METHODS: We searched PubMed, Embase, Web of Science, ClinicalTrials.gov, China National Knowledge Infrastructure (CNKI), and SinoMed databases for eligible studies that investigated the influence of uterine fibroids on adverse outcomes in pregnancy. The pooled risk ratio (RR) of the variables was estimated with fixed effect or random effect models. RESULTS: Twenty-four studies with 237 509 participants were included. The pooled results showed that fibroids elevated the risk of adverse outcomes, including preterm birth, cesarean delivery, placenta previa, miscarriage, preterm premature rupture of membranes (PPROM), placental abruption, postpartum hemorrhage (PPH), fetal distress, malposition, intrauterine fetal death, low birth weight, breech presentation, and preeclampsia. However, after adjusting for the potential factors, negative effects were only seen for preterm birth, cesarean delivery, placenta previa, placental abruption, PPH, intrauterine fetal death, breech presentation, and preeclampsia. Subgroup analysis showed an association between larger fibroids and significantly elevated risks of breech presentation, PPH, and placenta previa in comparison with small fibroids. Multiple fibroids did not increase the risk of breech presentation, placental abruption, cesarean delivery, PPH, placenta previa, PPROM, preterm birth, and intrauterine growth restriction. Meta-regression analyses indicated that maternal age only affected the relationship between uterine fibroids and preterm birth, and BMI influenced the relationship between uterine fibroids and intrauterine fetal death. Other potential confounding factors had no impact on malposition, fetal distress, PPROM, miscarriage, placenta previa, placental abruption, and PPH. CONCLUSION: The presence of uterine fibroids poses increased risks of adverse pregnancy and obstetric outcomes. Fibroid size influenced the risk of breech presentation, PPH, and placenta previa, while fibroid numbers had no impact on the risk of these outcomes.

Risk Factors for Postpartum Hemorrhage in Severe Pre-Eclampsia: A Retrospective Single-Centre Study of 1953 Cases.

BACKGROUND Severe pre-eclampsia (sPE) and postpartum hemorrhage (PPH) in pregnancy have serious impact on maternal and fetal health and life. Co-occurrence of sPE and PPH often leads to poor pregnancy outcomes. We explored risk factors associated with PPH in women with sPE. MATERIAL AND METHODS This retrospective study included 1953 women with sPE who delivered at the Women's Hospital of Nanjing Medical University between April 2015 and April 2023. Risk factors for developing PPH in sPE were analyzed, and subgroups were analyzed by delivery mode (cesarean and vaginal). RESULTS A total of 197 women with PPH and 1756 women without PPH were included. Binary logistic regression results showed twin pregnancy (P<0.001), placenta accreta spectrum disorders (P=0.045), and placenta previa (P<0.001) were independent risk factors for PPH in women with sPE. Subgroup analysis showed risk factors for PPH in cesarean delivery group were the same as in the total population, but vaginal delivery did not reduce risk of PPH. Spinal anesthesia reduced risk of PPH relative to general anesthesia (P=0.034). Vaginal delivery group had no independent risk factors for PPH; however, magnesium sulfate (P=0.041) reduced PPH incidence. CONCLUSIONS Women with twin pregnancy, placenta accreta spectrum disorders, placenta previa, and assisted reproduction with sPE should be alerted to the risk of PPH, and spinal anesthesia should be preferred in cesarean delivery. Magnesium sulfate should be used aggressively in women with sPE; however, the relationship between magnesium sulfate and PPH risk needs further investigation.

Placental T2WI MRI-based radiomics-clinical nomogram predicts suspicious placenta accreta spectrum in patients with placenta previa.

BACKGROUND: The incidence of placenta accreta spectrum (PAS) increases in women with placenta previa (PP). Many radiologists sometimes cannot completely and accurately diagnose PAS through the simple visual feature analysis of images, which can affect later treatment decisions. The study is to develop a T2WI MRI-based radiomics-clinical nomogram and evaluate its performance for non-invasive prediction of suspicious PAS in patients with PP. METHODS: The preoperative MR images and related clinical data of 371 patients with PP were retrospectively collected from our hospital, and the intraoperative examination results were used as the reference standard of the PAS. Radiomics features were extracted from sagittal T2WI MR images and further selected by LASSO regression analysis. The radiomics score (Radscore) was calculated with logistic regression (LR) classifier. A nomogram integrating Radscore and selected clinical factors was also developed. The model performance was assessed with respect to discrimination, calibration and clinical usefulness. RESULTS: A total of 6 radiomics features and 1 clinical factor were selected for model construction. The Radscore was significantly associated with suspicious PAS in both the training (p < 0.001) and validation (p < 0.001) datasets. The AUC of the nomogram was also higher than that of the Radscore in the training dataset (0.891 vs. 0.803, p < 0.001) and validation dataset (0.897 vs. 0.780, p < 0.001), respectively. The calibration was good, and the decision curve analysis demonstrated the nomogram had higher net benefit than the Radscore. CONCLUSIONS: The T2WI MRI-based radiomics-clinical nomogram showed favorable diagnostic performance for predicting PAS in patients with PP, which could potentially facilitate the obstetricians for making clinical decisions.

Accuracy of Ultrasound in the Prediction of the FIGO Classification of Placenta Accreta Spectrum.

OBJECTIVES: To evaluate the accuracy of greyscale ultrasound (US) and colour Doppler detecting placenta accreta spectrum (PAS) based on the newly recommended International Federation of Obstetrics and Gynaecology (FIGO) grading system. METHODS: This prospective study was conducted on women diagnosed with placenta previa or low-lying placenta involving the anterior uterine wall and associated with PAS as identified by the US. Transabdominal and transvaginal greyscale US was performed on admission between 34 and 36 weeks of gestation and compared to clinical grading and histopathological examination after cesarean hysterectomy. RESULTS: In total, 36 pregnant females who underwent a cesarean hysterectomy due to placenta previa complicated by PAS were included in this study. All patients had a history of previous cesarean deliveries, ranging from 1 to 5 deliveries. The US has an overall sensitivity of 33%, 55%, and 84.62%, and specificity of 100%, 75%, and 60% in detecting the 3 degrees of PAS, respectively. US cannot differentiate between the different subtypes of PAS grade 3 (a, b, and c). CONCLUSION: The overall US evaluation was highly significant in predicting the FIGO diagnosis of PAS; however, all ultrasonographic signs were equally relevant in diagnosing grade 1 and/or 2 PAS and were inaccurate in differing the subtypes of PAS grade 3.