Abstract

BACKGROUND Growing evidence suggests low and high maternal hemoglobin (Hb) concentrations may have adverse consequences for maternal and child health. There remain questions on specific Hb thresholds to define anemia and high Hb as well as how cutoffs may vary by anemia etiology and timing of assessment. METHODS We conducted an updated systematic review (using PubMed and Cochrane Review) on low (< 110 g/L) and high (≥ 130 g/L) maternal Hb concentrations and associations with a range of maternal and infant health outcomes. We examined associations by timing of Hb assessment (preconception; first, second, and third trimesters, as well as at any time point in pregnancy), varying cutoffs used for defining low and high hemoglobin concentrations and performed stratified analyses by iron-deficiency anemia. We conducted meta-analyses to obtain odds ratios (OR) and 95% confidence intervals. RESULTS The updated systematic review included 148 studies. Low maternal Hb at any time point in pregnancy was associated with: low birthweight, LBW (OR (95% CI) 1.28 (1.22-1.35)), very low birthweight, VLBW (2.15 (1.47-3.13)), preterm birth, PTB (1.35 (1.29-1.42)), small-for-gestational age, SGA (1.11 (1.02-1.19)), stillbirth 1.43 (1.24-1.65)), perinatal mortality (1.75 (1.28-2.39)), neonatal mortality (1.25 (1.16-1.34), postpartum hemorrhage (1.69 (1.45-1.97)), transfusion (3.68 (2.58-5.26)), pre-eclampsia (1.57 (1.23-2.01)), and prenatal depression (1.44 (1.24-1.68)). For maternal mortality, the OR was higher for Hb < 90 (4.83 (2.17-10.74)) than for Hb < 100 (2.87 (1.08-7.67)). High maternal Hb was associated with: VLBW (1.35 (1.16-1.57)), PTB (1.12 (1.00-1.25)), SGA (1.17 (1.09-1.25)), stillbirth (1.32 (1.09-1.60)), maternal mortality (2.01 (1.12-3.61)), gestational diabetes (1.71 (1.19-2.46)), and pre-eclampsia (1.34 (1.16-1.56)). Stronger associations were noted earlier in pregnancy for low Hb and adverse birth outcomes while the role of timing of high Hb was inconsistent. Lower Hb cutoffs were associated with greater odds of poor outcomes; for high Hb, data were too limited to identify patterns. Information on anemia etiology was limited; relationships did not vary by iron-deficiency anemia. CONCLUSION Both low and high maternal Hb concentrations during pregnancy are strong predictors of adverse maternal and infant health outcomes. Additional research is needed to establish healthy reference ranges and design effective interventions to optimize maternal Hb during pregnancy.

Abstract

INTRODUCTION Placental transfusion strategies in preterm newborns have not been evaluated in low- and middle-income countries (LMICs). The objective of this systematic review was to compare placental transfusion strategies in preterm newborns in LMICs, including delayed cord clamping (DCC) for various time intervals, DCC until cord pulsations stop, umbilical cord milking, and immediate cord clamping (ICC). METHODS Medline, Embase, CINAHL, and CENTRAL were searched from inception. Observational studies and randomized controlled trials (RCTs) were included. Two authors independently extracted data for Bayesian random-effects network meta-analysis (NMA) if more than 3 interventions reported an outcome or a pairwise meta-analysis was utilized. RESULTS Among newborns <34 weeks of gestation, NMA of 9 RCTs could not rule out benefit or harm for survival from DCC 30-60 s compared to ICC: relative risk (RR) (95% credible interval) 0.96 (0.78-1.12), moderate certainty, or any included strategy compared to each other (low to very low certainty). Among late preterm newborns, DCC 120 s might be associated with improved survival: RR (95% confidence interval) 1.11 (1.01-1.22), very low certainty. We could not detect differences in the risk of intraventricular hemorrhage grade > II and bronchopulmonary dysplasia for any included intervention (low to very low certainty). DCC 60 s and 120 s might improve the hematocrit level among all preterm newborns (very low certainty), and DCC 45 s may decrease the risk of receipt of inotropes among newborns <34 weeks of gestation (low certainty). CONCLUSIONS In LMICs, DCC for 60 s and 120 s might improve hematocrit level in preterm newborns, and DCC for 45 s may decrease the risk of receipt of inotropes in newborns <34 weeks, with no conclusive effect on survival.

Abstract

OBJECTIVE To compare the rates of adverse outcomes with postpartum hemorrhage (PPH) before and after implementation of drills or simulation exercises. STUDY ELIGIBILITY CRITERIA We included all English studies that reported on rates of PPH and associated complications during the pre- and post-implementation of interventional exercises. STUDY APPRASIAL AND SYNTHESIS METHODS Two investigators independently reviewed the abstracts, and full articles for eligibility of all studies. Inconsistencies related to study evaluation or data extraction were resolved by a third author. The co-primary outcomes were the rate of PPH and of any transfusion; the secondary outcomes included admission to the intensive care unit (ICU), transfusion ≥ 4 units of packed red blood cells, hysterectomy, or maternal death. Study effects were combined by Bayesian meta-analysis and reported as risk ratios (RR) and 95% credible intervals (Cr). RESULTS We reviewed 142 full length articles. Of these, 18 publications, with 355,060 deliveries-150,562 (42%) deliveries during the pre-intervention and 204,498 (57.6%) deliveries in the post-interventional period-were included in the meta-analysis. Using the Newcastle-Ottawa Scale, only three studies were considered good quality, and none of them were done in the US. The rate of PPH prior to intervention was 5.06% and 5.46% afterwards (RR 1.09, 95% CI 0.87-1.36; probability of reduction in the diagnosis being 21%). The likelihood of transfusion decreased from 1.68% in the pre-intervention to 1.27% in the post-intervention period (RR 0.80, 95% Cr 0.57-1.09). The overall probability of reduction in transfusion was 93%, albeit it varied among studies done in non-US countries (96%) versus in the US (23%). Transfusion of 4 units or more of blood occurred in 0.44% of deliveries before intervention and 0.37% afterwards (RR of 0.85, 95% CI 0.50-1.52), with the overall probability of reduction being 72% (76% probability of reduction in studies from non-US countries and 49% reduction with reports from the US). Surgical interventions to manage PPH, which was not reported in any US studies, occurred in 0.14% before intervention and 0.28% afterwards (RR 1.29; 95% CI 0.56-3.06; probability of reduction 27%). Admission to the ICU occurred in 0.10% before intervention and 0.08% subsequently (RR 0.92, 95% CI 0.58-1.43), with the overall probability of reduction being 65% (81% in studies from non-US countries and 27% from the study done in the US). Maternal death occurred in 0.17% in the pre-intervention period and 0.09% during the post-intervention (RR 0.62, 95% CI 0.33-1.05; probability of reduction 93% in studies from non-US countries and 82% in one study from the US). CONCLUSIONS Interventions to reduce the sequelae of PPH are associated with decrease in adverse outcomes. The conclusion, however, ought not to be accepted reflexively for the US population. All of the studies on the topic done in the US are of poor quality and the associated probability of reduction in sequelae are consistently lower than those done in other countries. SYNOPSIS Since the putative benefits of PPH drills or simulation exercises are based on poor quality pre- and post-intervention trials, policies recommending them ought to be revisited.

Abstract

BACKGROUND Postpartum haemorrhage (PPH) remains a leading cause of maternal mortality and morbidity worldwide, and the rate is increasing. Using a reliable predictive model could identify those at risk, support management and treatment, and improve maternal outcomes. AIMS To systematically identify and appraise existing prognostic models for PPH and ascertain suitability for clinical use. MATERIALS AND METHODS MEDLINE, CINAHL, Embase, and the Cochrane Library were searched using combinations of terms and synonyms, including 'postpartum haemorrhage', 'prognostic model', and 'risk factors'. Observational or experimental studies describing a prognostic model for risk of PPH, published in English, were included. The Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies checklist informed data extraction and the Prediction Model Risk of Bias Assessment Tool guided analysis. RESULTS Sixteen studies met the inclusion criteria after screening 1612 records. All studies were hospital settings from eight different countries. Models were developed for women who experienced vaginal birth (n = 7), caesarean birth (n = 2), any type of birth (n = 2), hypertensive disorders (n = 1) and those with placental abnormalities (n = 4). All studies were at high risk of bias due to use of inappropriate analysis methods or omission of important statistical considerations or suboptimal validation. CONCLUSIONS No existing prognostic models for PPH are ready for clinical application. Future research is needed to externally validate existing models and potentially develop a new model that is reliable and applicable to clinical practice.

Abstract

INTRODUCTION Postpartum hemorrhage (PPH) has remained the leading cause of maternal mortality. While anemia is a leading contributor to maternal morbidity, molecular, cellular and anemia-induced hypoxia, clinical studies of the relationship between prenatal-anemia and PPH have reported conflicting results. Therefore, our objective was to investigate the outcomes of studies on the relationships between prenatal anemia and PPH-related mortality. MATERIALS AND METHODS Electronic databases (MEDLINE, Scopus, ClinicalTrials.gov, PROSPERO, EMBASE, and the Cochrane Central Register of Controlled Trials) were searched for studies published before August 2019. Keywords included "anemia," "hemoglobin," "postpartum hemorrhage," and "postpartum bleeding." Only studies involving the association between anemia and PPH were included in the meta-analysis. Our primary analysis used random effects models to synthesize odds-ratios (ORs) extracted from the studies. Heterogeneity was formally assessed with the Higgins' I(2) statistics, and explored using meta-regression and subgroup analysis. RESULTS We found 13 eligible studies investigating the relationship between prenatal anemia and PPH. Our findings suggest that severe prenatal anemia increases PPH risk (OR = 3.54; 95% CI: 1.20, 10.4, p-value = 0.020). There was no statistical association with mild (OR = 0.60; 95% CI: 0.31, 1.17, p-value = 0.130), or moderate anemia (OR = 2.09; 95% CI: 0.40, 11.1, p-value = 0.390) and the risk of PPH. CONCLUSION Severe prenatal anemia is an important predictive factor of adverse outcomes, warranting intensive management during pregnancy. PROSPERO Registration Number: CRD42020149184; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=149184.

Abstract

Hemolytic disease of fetus and newborn (HDFN) imposes great healthcare burden being associated with maternal alloimmunization against parental-inherited fetal red blood cell antigens causing fetal anemia or death. Noninvasive prenatal analysis (NIPT) provides safe fetal RHD genotyping for early identification of risk pregnancies and proper management guidance. We aimed to conduct systematic review and meta-analysis on NIPT's beneficial application, in conjunction with quantitative maternal alloantibody analysis, for early diagnosis of pregnancies at risk. Search for relevant articles was done in; PubMed/Medline, Scopus, and Ovid (January 2006April 2020), including only English-written articles reporting reference tests and accuracy data. Nineteen eligible studies were critically appraised. NIPT was estimated highly sensitive/specific for fetal RHD genotyping beyond 11-week gestation. Amplifications from ≥2 exons are optimum to increase accuracy. NIPT permits cost-effectiveness, precious resources sparing, and low emotional stress. Knowledge of parental ethnicity is important for correct NIPT result interpretations and quantitative screening. Cut-off titer ≥8-up-to-32 is relevant for anti-D alloantibodies, while, lower titer is for anti-K. Alloimmunization is influenced by maternal RHD status, gravida status, and history of adverse obstetrics. In conclusion, NIPT allows evidence-based provision of routine anti-D immunoprophylaxis and estimates potential fetal risks for guiding further interventions. Future large-scale studies investigating NIPT's non-RHD genotyping within different ethnic groups and in presence of clinically significant alloantibodies are needed.

Abstract

OBJECTIVES To explore how childbirth-related blood loss is evaluated and excessive bleeding recognised; and develop and test a theory of postpartum haemorrhage (PPH) diagnosis. DESIGN Two-phase, exploratory, sequential mixed methods design using focus groups, interviews and a pilot, randomised crossover study. SETTING Two hospitals in North West England. SAMPLE Women (following vaginal birth with and without PPH), birth partners, midwives and obstetricians. METHODS Phase 1 (qualitative): 8 focus groups and 20 one-to-one, semi-structured interviews were conducted with 15 women, 5 birth partners, 11 obstetricians, 1 obstetric anaesthetist and 19 midwives (n=51). Phase 2 (quantitative): 11 obstetricians and 10 midwives (n=21) completed two simulations of fast and slow blood loss using a high-fidelity childbirth simulator. RESULTS Responses to blood loss were described as automatic, intuitive reactions to the speed, nature and visibility of blood flow. Health professionals reported that quantifying volume was most useful after a PPH diagnosis, to validate intuitive decisions and guide on-going management. During simulations, PPH treatment was initiated at volumes at or below 200ml (fast mean blood loss 79.6ml, SD 41.1; slow mean blood loss 62.6ml, SD 27.7). All participants treated fast, visible blood loss, but only half treated slow blood loss, despite there being no difference in volumes (difference 18.2ml, 95% CI -5.6 to 42.2ml, p=0.124). CONCLUSIONS Experience and intuition, rather than blood loss volume, inform recognition of excessive blood loss after birth. Women and birth partners want more information and open communication about blood loss. Further research exploring clinical decision-making and how to support it is required.

Abstract

BACKGROUND Postpartum anemia can negatively affect maternal health and interfere with early parenting. Thus, it is important to have clear, evidence-informed recommendations on its diagnosis and treatment. OBJECTIVE To compare global recommendations regarding the appropriate management of postpartum anemia and to highlight similarities and differences. METHODS Systematic searches were conducted in the databases PubMed, CINAHL, LILACS, TRIP database, and Scopus, and in the websites of health institutions and scientific societies. Search terms were related to anemia and the postpartum period. Two hundred and eighty papers were identified; the full texts of 30 sets of guidelines were reviewed, with seven being included in the final analysis. Recommendations were extracted through an evaluation of the evidence on the definition, screening, and diagnosis of anemia. The quality of the guidelines was assessed using the AGREE II instrument. RESULTS Two sets of guidelines have been elaborated by international organizations, and the rest were produced by professional associations within high-resource countries. The discrepancies found in the guidelines are important and affect the definition of anemia, the criteria for screening asymptomatic women, or the criteria guiding treatment. The quality of the guidelines commonly scored between 4 and 6 on a scale of 0 to 7. Recommendations with poor-quality evidence predominated over recommendations with high-quality evidence. CONCLUSIONS This review highlights the need to reach a consensus on the definition of postpartum anemia, to agree on what constitutes a problem for maternal health, and to provide recommendations that reach greater consensus on its diagnosis and treatment.

Abstract

BACKGROUND Early administration of the antifibrinolytic drug tranexamic acid reduces death from bleeding in trauma and postpartum haemorrhage. We examined how the effectiveness and safety of antifibrinolytic drugs varies by the baseline risk of death as a result of bleeding. METHODS We performed an individual patient-level data meta-analysis of randomised trials including more than 1000 patients that assessed antifibrinolytics in acute severe bleeding. We identified trials performed between January 1, 1946 and July 5, 2018 (PROSPERO, number 42016052155). RESULTS Two randomised trials were selected where 28 333 patients received tranexamic acid treatment within 3 h after the onset of acute bleeding. Baseline characteristics to estimate the risk of death as a result of bleeding were divided into four categories: Low (0-5%), intermediate (6-10%), high (11-20%), and very high (>20%). Most patients had a low baseline risk of death as a result of bleeding (23 008 [81%]). Deaths as a result of bleeding occurred in all baseline risk categories with 240 (1%), 202 (8%), 232 (14%), and 357 (30%) deaths in the low-, intermediate-, high-, and very high-risk categories, respectively. The effectiveness of tranexamic acid did not vary by baseline risk when given within 3 h after bleeding onset (P=0.51 for interaction term). There was no increased risk of vascular occlusive events with tranexamic acid and it did not vary by baseline risk categories (P=0.25). CONCLUSIONS Tranexamic acid appears to be safe and effective regardless of baseline risk. Because many deaths are in patients at low and intermediate risk, tranexamic acid use should not be restricted to the most severely injured or bleeding patients.

Abstract

Globally, obstetric haemorrhage (OH) remains the leading cause of maternal mortality. Much of the associated mortality is ascribed to challenges surrounding deployment of innovations rather than lack of availability. In low- and middle-income countries (LMICs), where the burden is highest, there is a growing interest in implementation research as a means to bridge the 'know-do' gap between proven interventions and their reliable implementation at scale. In this systematic review, we identified and synthesized qualitative and quantitative data across the implementation outcomes of OH prevention innovations in LMICs using a taxonomy developed by Proctor et al. We also identified service outcomes for the included innovations, as well as implementation strategies and implementation facilitators and barriers. Eligible studies were empirical, focused on the implementation of OH prevention programmes or policies and occurred in an LMIC. Eight databases were searched. Two authors independently assessed studies for selection and extracted data; the first author resolved discrepancies. Narrative synthesis was used to analyse and interpret the findings. Studies were predominantly focused in Africa and on primary prevention. Interventions included prophylactic use of uterotonics (n = 7), clinical provider skills training (n = 4) and provision of clinical guidelines (n = 1); some (n = 3) were also part of a multi-component quality improvement bundle. Various barriers were reported, including challenges among intervention beneficiaries, providers and within the health system; however, studies reported the development and testing of practical implementation solutions. These included training and monitoring of implementers, community and stakeholder engagement and guidance by external mentors. Some studies linked successful delivery to implementation outcomes, most commonly adoption and acceptability, but also feasibility, penetration and sustainability. Findings suggest that innovations to prevent OH can be acceptable, appropriate and feasible in LMIC settings; however, more research is needed to better evaluate these and other under-reported implementation outcomes.