-
American Journal of Obstetrics and... Oct 2019Elective induction of labor at 39 weeks among low-risk nulliparous women has reduced the chance of cesarean and other adverse maternal and perinatal outcomes in a... (Comparative Study)
Comparative Study Meta-Analysis
BACKGROUND
Elective induction of labor at 39 weeks among low-risk nulliparous women has reduced the chance of cesarean and other adverse maternal and perinatal outcomes in a randomized trial, although its clinical effectiveness in nonresearch settings remains uncertain.
OBJECTIVE
To perform a systematic review of observational studies that compared elective induction of labor at 39 weeks among nulliparous women with expectant management and to use meta-analytic techniques to estimate the association of elective induction with cesarean delivery, as well as other maternal and perinatal outcomes.
STUDY DESIGN
Studies were eligible for this meta-analysis only if they: (1) were observational; (2) compared women undergoing labor induction at 39 weeks with women undergoing expectant management beyond that gestational age; (3) included women in the induction group only if they had no other indication for labor induction at 39 weeks; and (4) provided data specifically for nulliparous women. The predefined primary outcome was cesarean delivery, and secondary outcomes representing other maternal and perinatal morbidities also were evaluated. Outcome data from different studies were combined to estimate pooled relative risks with 95% confidence intervals using random-effects models.
RESULTS
Of 375 studies identified by the initial search, 6 cohort studies, which included 66,019 women undergoing elective labor induction at 39 weeks and 584,390 undergoing expectant management, met inclusion criteria. Elective induction of labor at 39 weeks was associated with a significantly lower frequency of cesarean delivery (26.4% vs 29.1%; relative risk, 0.83; 95% confidence interval, 0.74-0.93), as well as of peripartum infection (2.8% vs 5.2%; relative risk, 0.53; 95% confidence interval, 0.39-0.72). Neonates of women in the induction group were less likely to have respiratory morbidity (0.7% vs 1.5%; relative risk, 0.71; 95% confidence interval, 0.59-0.85); meconium aspiration syndrome (0.7% vs 3.0%; relative risk, 0.49; 95% confidence interval, 0.26-0.92); and neonatal intensive care unit admission (3.5% vs 5.5%; relative risk, 0.80; 95% confidence interval, 0.72-0.88). There also was a lower risk of perinatal mortality (0.04% vs 0.2%; relative risk, 0.27; 95% confidence interval, 0.09-0.76).
CONCLUSION
This meta-analysis of 6 cohort studies demonstrates that elective induction of labor at 39 weeks, compared with expectant management beyond that gestational age, was associated with a significantly lower risk of cesarean delivery, maternal peripartum infection, and perinatal adverse outcomes, including respiratory morbidity, intensive care unit admission, and mortality.
Topics: Cesarean Section; Chorioamnionitis; Cohort Studies; Continuous Positive Airway Pressure; Endometritis; Female; Humans; Infant, Newborn; Intensive Care Units, Neonatal; Labor, Induced; Lacerations; Meconium Aspiration Syndrome; Observational Studies as Topic; Oxygen Inhalation Therapy; Parity; Perinatal Mortality; Perineum; Postpartum Hemorrhage; Pregnancy; Respiration, Artificial; Respiratory Insufficiency; Surgical Wound Infection; Watchful Waiting
PubMed: 30817905
DOI: 10.1016/j.ajog.2019.02.046 -
International Journal of Gynaecology... Jun 2024Placenta accreta spectrum (PAS) disorder is a critical and severe obstetric condition associated with high risk of intraoperative massive hemorrhage and cesarean... (Review)
Review
Clinical evaluation of the effect for prophylactic balloon occlusion in pregnancies complicated with placenta accreta spectrum disorder: A systematic review and meta-analysis.
BACKGROUND
Placenta accreta spectrum (PAS) disorder is a critical and severe obstetric condition associated with high risk of intraoperative massive hemorrhage and cesarean hysterectomy. Severe obstetric hemorrhage is currently one of the leading causes of maternal death worldwide. Prophylactic balloon occlusions, including prophylactic balloon occlusion of the abdominal aorta (PBOAA) and prophylactic balloon occlusion of the internal iliac arteries (PBOIIA), are the most common means of controlling hemorrhage in patients with PAS disorder, but their effectiveness is still debated.
OBJECTIVE
A systematic review and meta-analysis were conducted to evaluate the clinical effectiveness of prophylactic balloon occlusion during cesarean section (CS) in improving maternal outcomes for PAS patients.
SEARCH STRATEGY
MEDLINE, EMBASE, OVID, PubMed and the Cochrane Library were systematically searched from the inception dates to June 2022, using the keywords "placenta accreta spectrum disorder/morbidly adherent placenta (placenta previa, placenta accreta, placenta increta, placenta percreta), balloon occlusion, internal iliac arteries, abdominal aorta, hemorrhage, hysterectomy, estimated blood loss (EBL), packed red blood cells (PRBCs)" to identify the systematic reviews or meta-analyses.
SELECTION CRITERIA
All articles regarding PAS disorders and including the application of balloon occlusion were included in the screening.
DATA COLLECTION AND ANALYSIS
Two independent researchers performed the data extraction and assessed study quality. EBL volume and PRBC transfusion volume was regarded as the primary endpoints. Random and fixed effects models were used for the meta-analysis (RRs and 95% CIs), and the Newcastle-Ottawa Scale was used for quality assessments.
MAIN RESULTS
Of 429 studies identified, a total of 35 trials involving the application of balloon occlusion for patients with PAS disorder during CS were included. A total of 19 studies involving 935 patients who underwent PBOIIA were included in the PBOIIA group, and 851 patients were included in control 1 group. Ten studies including 428 patients with PAS who underwent PBOAA were allocated to the PBOAA group, and 324 patients without PBOAA were included in control 2 group. Simultaneously, we compared the effect on PBOAA and PBOIIA including seven studies, which referred to 267 cases in the PBOAA group and 313 cases in the PBOIIA group. The results showed that the PBOIIA group had a reduced EBL volume (MD: 342.06 mL, 95% CI: -509.90 to -174.23 mL, I = 77%, P < 0.0001) and PRBC volume (MD: -1.57 U, 95% CI: -2.49 to -0.66 U, I = 91%, P = 0.0008) than that in control 1 group. With regard to the EBL volume (MD: -926.42 mL, 95% CI: -1437.07 to -415.77 mL, I = 96%, P = 0.0004) and PRBC transfusion volume (MD: -2.42 U, 95% CI: -4.25 to -0.59 U, I = 99%, P = 0.009) we found significant differences between the PBOAA group and control 2 group. Prophylactic balloon occlusion (PBOAA and PBOIIA) had a significant effect on reducing intraoperative blood loss and blood transfusion volume in patients with PAS. Moreover, PBOAA was more effective than PBOIIA in reducing intraoperative blood loss (MD: -406.63 mL, 95% CI: -754.12 to -59.13 mL, I = 92%, P = 0.020), but no significant difference in controlling PRBCs (MD: -3.48 U, 95% CI: -8.90 to 1.95 U, I = 99%, P = 0.210) between the PBOIIA group and the PBOAA group. Hierarchical analysis was conducted by differentiating gestational weeks and maternal age to reduce the high heterogeneity of meta-analysis. Hierarchical analysis results demonstrated the heterogeneities of the study were reduced to some extent, and gestational weeks and maternal age might be the cause of increased heterogeneity.
CONCLUSION
Prophylactic balloon occlusion is a safe and effective method to control hemorrhage and reduce PRBC transfusion volume for patients with PAS, and PBOAA could reduce more intraoperative blood loss than PBOIIA. However, we found no statistical difference in lessening packed red blood cell transfusion volume for PAS patients. Hence, preoperative prophylactic balloon occlusion is the recommended application for PAS patients in obstetric CSs. Furthermore, PBOAA is preferred for controlling intraoperative bleeding in patients with corresponding medical conditions.
PubMed: 38899567
DOI: 10.1002/ijgo.15704 -
Scientific Reports Jan 2017Antepartum hemorrhage (APH) is an important cause of perinatal mortality and maternal morbidity in pregnant women with placenta previa in the world. However, the... (Meta-Analysis)
Meta-Analysis Review
Antepartum hemorrhage (APH) is an important cause of perinatal mortality and maternal morbidity in pregnant women with placenta previa in the world. However, the epidemiological characteristics are not completely understood. We performed an initial systematic review and meta-analysis to assess the prevalence of APH in pregnant women with placenta previa. It was totally performed following the Preferred Reporting Items for Systematic reviews and Meta-Analysis statement. PubMed, Elsevier Science Direct, and the Cochrane Library were searched before April 2016. A meta-analysis with a random-effects model based on a proportions approach was performed to determine the prevalence. Stratified analyses, meta-regression method, and sensitivity analysis were utilized to analyze the heterogeneity. A total of 29 articles were included. The pooled overall prevalence of APH among pregnant women with placenta previa was 51.6% (95% CI 42.7-60.6) in a heterogeneous set of studies (I = 97.9). Correlation analysis found that there was a positive correlation between prevalence and percentage of multiparous (r = 0.534, P = 0.027) and a negative correlation between prevalence and survey year (r = -0.400, P = 0.031). In conclusion, the prevalence of APH was a high condition among pregnant women with placenta previa.
Topics: Adult; Female; Humans; Parity; Placenta Previa; Pregnancy; Prevalence; Regression Analysis; Uterine Hemorrhage
PubMed: 28067303
DOI: 10.1038/srep40320 -
Medicine Oct 2016Placenta previa is characterized by the abnormal placenta overlying the endocervical os, and it is known as one of the most feared adverse maternal and fetal-neonatal... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Placenta previa is characterized by the abnormal placenta overlying the endocervical os, and it is known as one of the most feared adverse maternal and fetal-neonatal complications in obstetrics.
OBJECTIVES
We aimed to obtain overall and regional estimates of placenta previa prevalence among deliveries in Mainland China.
METHODS
The research was performed a systematic review, following the Meta-analysis of observational studies in epidemiology (MOOSE) guidelines for systematic reviews of observational studies, and the preferred reporting items for systematic reviews and meta-analysis (PRISMA) statement for reporting systematic reviews and meta-analysis. Electronic databases were searched and included hospital-based studies that reported placenta previa prevalence in Mainland China. Random-effects meta-analyses were used to pool prevalence estimates of placenta previa. Meta-regression analyses were performed to explore sources of heterogeneity across the included studies. For exploring the geographical distributions of placenta previa, the ArcGIS software (Esri) was used to construct the map of prevalence.
RESULTS
A total of 80 articles and 86 datasets (including 1,298,548 subjects and 14,199 placenta previa cases) from 1965 through 2015 were included. The pooled overall prevalence of placenta previa among deliveries was 1.24% (95% confidence interval [CI], 1.12-1.36) in Mainland China during 1965 to 2015. And, the trend in the prevalence of placenta previa was steady. The occurrence rate of placenta previa in the region groups Northeast, North, Northwest, Central China, East, South, and Southwest was 1.20%, 1.01%, 1.10%, 1.15%, 0.93%, 1.42%, and 2.01%, respectively. The prevalence map based on a geographic information system showed an unequal geographic distribution.
CONCLUSIONS
The results showed that placenta previa is currently a high-burden disease in Mainland China. This review would be useful for the design of placenta previa planning and implementation adequate health care systems and treatment programs in Mainland China.
Topics: China; Delivery, Obstetric; Female; Humans; Placenta Previa; Pregnancy; Prevalence
PubMed: 27749592
DOI: 10.1097/MD.0000000000005107 -
Hypertension in Pregnancy Aug 2018Previous studies have reported a positive association between hypertensive disorders complicating pregnancy and placenta accreta. However, whether hypertensive disorders... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
Previous studies have reported a positive association between hypertensive disorders complicating pregnancy and placenta accreta. However, whether hypertensive disorders complicating pregnancy associated with placenta accreta is still not clear. The objective was to systematically review the literature to determine a possible association between hypertensive disorders complicating pregnancy and placenta accreta.
METHODS
A systematic search of PubMed database, the Cochrane Library, Willy Online Library, and ScienceDirect database through 1st December 2015, was conducted. Two authors independently assessed data extraction and quality of the studies using the Newcastle-Ottawa Scale. Assessment of heterogeneity and analysis of data were operated by Review Manager 5.3.0.
RESULTS
Three studies involving 4174 patients who developed hypertensive disorders complicating pregnancy of a total of 38,004 pregnant women were selected. The result of our meta-analysis revealed that pregnancy induced hypertension was significantly associated with a reduction of placenta accreta (OR = 0.50, 95% CI: 0.30-0.82; heterogeneity: I = 13%, p = 0.32).
CONCLUSIONS
Our meta-analysis demonstrated that the risk of placenta accreta is reduced in women with hypertensive disorders complicating pregnancy. Further well-designed studies are warranted to testify the result and explored any potential mechanism association between hypertensive disorders complicating pregnancy and placenta accreta.
Topics: Female; Humans; Hypertension, Pregnancy-Induced; Placenta Accreta; Pregnancy; Risk
PubMed: 30040502
DOI: 10.1080/10641955.2018.1498880 -
American Journal of Obstetrics and... Sep 2019The objective of this study was to evaluate the prevalence of placenta accreta spectrum in general population studies and the main maternal outcomes at delivery. (Meta-Analysis)
Meta-Analysis
OBJECTIVE DATA
The objective of this study was to evaluate the prevalence of placenta accreta spectrum in general population studies and the main maternal outcomes at delivery.
STUDY
We searched PubMed, Google Scholar, clinicalTrials.gov, and MEDLINE between 1982 and 2018. Articles that provided data on the number of cases of placenta accreta spectrum per pregnancies, births, or deliveries in a defined population were used.
STUDY APPRAISAL AND SYNTHESIS METHODS
Study characteristics were evaluated by 2 independent reviewers who used a predesigned protocol. Primary outcomes were the prevalence of placenta accreta spectrum and clinical diagnostic data at birth; the pathologic criteria were used to confirm the diagnosis. Secondary outcomes included cases that required transfusion, incidence of peripartum hysterectomy, and maternal mortality rates. Heterogeneity between studies was analyzed with the Cochran's Q-test and the I statistics.
RESULTS
Of the 98 full-text studies that were identified, 29 articles met the defined criteria and included 22 retrospective and 7 prospective studies comprising 7001 cases of placenta accreta spectrum of 5,719,992 births. Prevalence rates ranged from 0.01-1.1% with an overall pooled prevalence of 0.17% (95% confidence interval, 0.14-0.19). Only 10 studies provided detailed histopathologic data. The pool prevalence for the adherent vs the invasive grades was 0.5 (95% confidence interval, 0.3-0.36) and 0.3 (95% confidence interval, 0.2-0.4) per 1000 births, respectively. The pooled incidence for peripartum hysterectomy was 52.2% (95% confidence interval, 38.3-66.4; I=99.8%) and 46.9% (95 % confidence interval, 34-59.9; I=98.8%) for hemorrhage that required transfusion. The pooled estimate of maternal death was 0.05% (95% confidence interval, 0.06-0.69; I=73%). We found large amounts of heterogeneity between studies for all parameters and further quantification was limited because of methodologic inconsistencies between studies with regards to clinical criteria that were used for the diagnosis of the condition at birth and the histopathologic confirmation of the diagnosis and differential diagnosis between adherent and invasive accreta placentation.
CONCLUSION
This meta-analysis indicated wide variation between studies for the prevalence rate of placenta accreta spectrum and for the different grades of accreta placentation that highlighted the need for consistency in definitions that are used to describe placenta accreta spectrum at birth and in the reporting of this increasing common obstetric complication.
Topics: Developed Countries; Developing Countries; Female; Global Health; Humans; Placenta Accreta; Pregnancy; Pregnancy Outcome; Prevalence; Prognosis; Retrospective Studies
PubMed: 30716286
DOI: 10.1016/j.ajog.2019.01.233 -
PloS One 2017The global burden of postpartum hemorrhage (PPH) in women with placenta previa is a major public health concern. Although there are different reports on the incidence of... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The global burden of postpartum hemorrhage (PPH) in women with placenta previa is a major public health concern. Although there are different reports on the incidence of PPH in different countries, to date, no research has reviewed them.
OBJECTIVE
The aim of this study was to calculate the average point incidence of PPH in women with placenta previa.
METHODS
A systematic review and meta-analysis of observational studies estimating PPH in women with placenta previa was conducted through literature searches in four databases in Jul 2016. This study was totally conducted according to the MOOSE guidelines and in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses standard.
RESULTS
From 1148 obtained studies, 11 included in the meta-analysis, which involved 5146 unique pregnant women with placenta previa. The overall pooled incidence of PPH was 22.3% (95% CI 15.8-28.7%). In the subgroup, the prevalence was 27.4% in placenta previas, and was 14.5% in low-lying placenta previa; the highest prevalence was estimated in Northern America (26.3%, 95%CI 11.0-41.6%), followed by the Asia (20.7%, 95%CI 12.8-28.6%), Australia (19.2%, 95% CI 17.2-21.1%) and Europe (17.8%, 95% CI, 11.5%-24.0%).
CONCLUSIONS
The summary estimate of the incidence of PPH among women with placenta previa was considerable in this systematic review. The results will be crucial in prevention, treatment, and identification of PPH among pregnant women with placenta previa and will be contributed to the planning and implantation of relevant public health strategies.
Topics: Adult; Female; Humans; Incidence; Placenta Previa; Postpartum Hemorrhage; Pregnancy
PubMed: 28107460
DOI: 10.1371/journal.pone.0170194 -
Computational and Mathematical Methods... 2022The disease burden and incidence of placenta accreta are increasing worldwide. The morbidity and mortality associated with undiagnosed placenta accreta are both high,... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The disease burden and incidence of placenta accreta are increasing worldwide. The morbidity and mortality associated with undiagnosed placenta accreta are both high, highlighting the important of early diagnosis and intervention. In recent years, increasing studies are exploring the diagnostic value of magnetic resonance imaging (MRI) for placenta accreta. Compared with traditional ultrasound, MRI has the advantages of high-resolution, multiangle imaging, and less influence by amniotic fluid and intestinal gas. However, the reported diagnostic accuracy among studies was inconsistent. Therefore, this study is aimed at exploring the diagnostic value of MRI for placenta accreta by systematic review and meta-analysis.
METHODS
Relevant literature were systematically searched in PubMed, Ovid, Embase, ScienceDirect database, CNKI, and Wanfang database by using medical subject headings and relevant diagnostic terminologies such as sensitivity, specificity, likelihood ratio, receiver-operating characteristic curve, and area under the curve. The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and area under the curve of the included literature were analyzed using stata 17.0 software. Publication bias of the included studies was assessed by Deek's funnel plot. Cochrane statistics and statistics were used to test the heterogeneity.
RESULTS
A total of 10 primary publications, comprising 4 retrospective studies and 6 prospective studies, were included in this meta-analysis. The gestational weeks of pregnant women ranged from 32 to 35 weeks, and the sample size ranged from 37 cases to 575 cases. Only 4 studies used the blind method in the process of clinical diagnosis by MRI. The combined sensitivity, specificity, and area of curve under summary receiver-operating characteristic for the diagnosis of placenta accreta by MRI were 0.88 (95% CI, 0.79-0.93), 0.79 (95% CI, 0.68-0.87), and 0.91 (95% CI, 0.88.-0.93), respectively. The combined positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and diagnostic score were 4.17 (95% CI, 2.62-6.66), 0.16 (95% CI, 0.09-0.29), 26.61 (95% CI, 10.22-69.28), and 3.28 (95% CI, 2.32-4.24), respectively. No publication bias was noted.
CONCLUSION
Diagnosis of placenta accreta by MRI has good accuracy and predictive value that warrants clinical promotion.
Topics: Female; Humans; Magnetic Resonance Imaging; Placenta Accreta; Pregnancy; Prospective Studies; Retrospective Studies; Sensitivity and Specificity
PubMed: 36060665
DOI: 10.1155/2022/2751559 -
BioMed Research International 2022This 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... (Meta-Analysis)
Meta-Analysis Review
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 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; = 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; = 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.
Topics: Chi-Square Distribution; Cohort Studies; Female; Humans; Observational Studies as Topic; Placenta Accreta; Pregnancy; Risk Factors; Smoking
PubMed: 35860796
DOI: 10.1155/2022/2399888 -
Medicine Apr 2017Abnormally invasive placenta (AIP) or placenta accreta (PA) is considered numerous adverse maternal and fetal-neonatal complications. There has been no detailed study to... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Abnormally invasive placenta (AIP) or placenta accreta (PA) is considered numerous adverse maternal and fetal-neonatal complications. There has been no detailed study to characterize the prevalence of AIP among deliveries in mainland China.
OBJECTIVES
We aimed to fill this gap and obtained overall and regional estimates of AIP prevalence via a systematic review and meta-analysis.
METHODS
This systematic review and meta-analysis was totally performed following the Meta-analysis of Observational Studies in Epidemiology guidelines for systematic reviews of observational studies, and the Preferred Reporting Items for Systematic reviews and Meta-Analysis statement for reporting systematic reviews and meta-analysis.
RESULTS
A total of 23 articles (including 350,939) were included. Most studies (22) focused on the placenta increta (PI), only 2 articles in PA, and none in placenta percreta (PP). In this meta-analysis, the overall prevalence of AIP was 0.22% (95% confidence interval 0.18%-0.27%) in a heterogeneous set of studies (I = 93.5%). In a subgroup, the prevalence of PA and PI was 0.48% and 0.23%, respectively. Stratified analyses of PI found that the prevalence was similar in North (0.23% [0.14%-0.32%]) and South (0.23% [0.15%-0.32%]), and lower in Central (0.20% [0.09-0.31%]); the inlanders (0.17% (0.12%-0.23%]) had a lower prevalence of PI than those living in coastal areas (0.24% [0.35%-0.63%]). As time goes on, the prevalence, from 0.03% (0.02%-0.04%) in 1970 to 1979 to 0.48% (0.30%-0.66%) in 2010 to present, was higher and higher. The different prevalence was also found in different in maternal age groups.
CONCLUSIONS
This first systematic review and meta-analysis found that the prevalence differed among different geographic areas and maternal age groups. The results would be useful for the design of abnormally invasive placenta planning and implementation adequate health care systems and treatment programs in mainland China.
Topics: China; Female; Humans; Maternal Age; Observational Studies as Topic; Placenta Accreta; Pregnancy; Prevalence; Residence Characteristics
PubMed: 28422862
DOI: 10.1097/MD.0000000000006636