Thromboprophylaxis during pregnancy and the puerperium: a systematic review and economic evaluation to estimate the value of future research.

Background: Pharmacological prophylaxis to prevent venous thromboembolism is currently recommended for women assessed as being at high risk of venous thromboembolism during pregnancy or in the 6 weeks after delivery (the puerperium). The decision to provide thromboprophylaxis involves weighing the benefits, harms and costs, which vary according to the individual's venous thromboembolism risk. It is unclear whether the United Kingdom's current risk stratification approach could be improved by further research. Objectives: To quantify the current decision uncertainty associated with selecting women who are pregnant or in the puerperium for thromboprophylaxis and to estimate the value of one or more potential future studies that would reduce that uncertainty, while being feasible and acceptable to patients and clinicians. Methods: A decision-analytic model was developed which was informed by a systematic review of risk assessment models to predict venous thromboembolism in women who are pregnant or in the puerperium. Expected value of perfect information analysis was used to determine which factors are associated with high decision uncertainty and should be the target of future research. To find out whether future studies would be acceptable and feasible, we held workshops with women who have experienced a blood clot or have been offered blood-thinning drugs and surveyed healthcare professionals. Expected value of sample information analysis was used to estimate the value of potential future research studies. Results: The systematic review included 17 studies, comprising 19 unique externally validated risk assessment models and 1 internally validated model. Estimates of sensitivity and specificity were highly variable ranging from 0% to 100% and 5% to 100%, respectively. Most studies had unclear or high risk of bias and applicability concerns. The decision analysis found that there is substantial decision uncertainty regarding the use of risk assessment models to select high-risk women for antepartum prophylaxis and obese postpartum women for postpartum prophylaxis. The main source of decision uncertainty was uncertainty around the effectiveness of thromboprophylaxis for preventing venous thromboembolism in women who are pregnant or in the puerperium. We found that a randomised controlled trial of thromboprophylaxis in obese postpartum women is likely to have substantial value and is more likely to be acceptable and feasible than a trial recruiting women who have had a previous venous thromboembolism. In unselected postpartum women and women following caesarean section, the poor performance of risk assessment models meant that offering prophylaxis based on these models had less favourable cost effectiveness with lower decision uncertainty. Limitations: The performance of the risk assessment model for obese postpartum women has not been externally validated. Conclusions: Future research should focus on estimating the efficacy of pharmacological thromboprophylaxis in pregnancy and the puerperium, and clinical trials would be more acceptable in women who have not had a previous venous thromboembolism. Study registration: This study is registered as PROSPERO CRD42020221094. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR131021) and is published in full in Health Technology Assessment; Vol. 28, No. 9. See the NIHR Funding and Awards website for further award information.

Women who are pregnant or who have given birth in the previous 6 weeks are at increased risk of developing blood clots that can cause serious illness or death. Small doses of blood thinners given by injection are safe in pregnancy and can reduce the risk of blood clots, but they can slightly increase the risk of bleeding. Healthcare professionals use risk assessment tools to decide if a woman is at high risk of blood clots and should be offered blood thinners. We wanted to find out what research would be useful to help them make better decisions. We reviewed previous research to establish which risk assessment tools are best at predicting who will have a blood clot. We then created a mathematical model to predict what would happen when using different risk assessment tools to decide who should be offered blood thinners, both during pregnancy and after giving birth. We found that there was a lot of uncertainty about which women should be offered blood thinners. This was mainly because there have only been a few small studies comparing blood thinners to no treatment in pregnant women or women who have recently given birth. We estimated the value of future studies comparing blood thinners to no treatment, in groups of women with different risk factors, by predicting what information we would gain and how this would be used to improve decisions about using blood thinners. To find out whether these studies would be acceptable and feasible, we held workshops with women who have experienced a blood clot or have been offered blood thinners and surveyed healthcare professionals. We found that a study in obese women who have recently given birth would have substantial value and may be more acceptable than a study in pregnant women with a previous blood clot.

Fetal loss and long-term maternal morbidity and mortality: A systematic review and meta-analysis.

BACKGROUND: Evidence suggests common pathways between pregnancy losses and subsequent long-term maternal morbidity, rendering pregnancy complications an early chronic disease marker. There is a plethora of studies exploring associations between miscarriage and stillbirth with long-term adverse maternal health; however, these data are inconclusive. METHODS AND FINDINGS: We systematically searched MEDLINE, EMBASE, AMED, BNI, CINAHL, and the Cochrane Library with relevant keywords and MeSH terms from inception to June 2023 (no language restrictions). We included studies exploring associations between stillbirth or miscarriage and incidence of cardiovascular, malignancy, mental health, other morbidities, and all-cause mortality in women without previous pregnancy loss. Studies reporting short-term morbidity (within a year of loss), case reports, letters, and animal studies were excluded. Study selection and data extraction were performed by 2 independent reviewers. Risk of bias was assessed using the Newcastle Ottawa Scale (NOS) and publication bias with funnel plots. Subgroup analysis explored the effect of recurrent losses on adverse outcomes. Statistical analysis was performed using an inverse variance random effects model and results are reported as risk ratios (RRs) with 95% confidence intervals (CIs) and prediction intervals (PIs) by combining the most adjusted RR, odds ratios (ORs) and hazard ratios (HRs) under the rare outcome assumption. We included 56 observational studies, including 45 in meta-analysis. There were 1,119,815 women who experienced pregnancy loss of whom 951,258 had a miscarriage and 168,557 stillbirth, compared with 11,965,574 women without previous loss. Women with a history of stillbirth had a greater risk of ischaemic heart disease (IHD) RR 1.56, 95% CI [1.30, 1.88]; p < 0.001, 95% PI [0.49 to 5.15]), cerebrovascular (RR 1.71, 95% CI [1.44, 2.03], p < 0.001, 95% PI [1.92, 2.42]), and any circulatory/cardiovascular disease (RR 1.86, 95% CI [1.01, 3.45], p = 0.05, 95% PI [0.74, 4.10]) compared with women without pregnancy loss. There was no evidence of increased risk of cardiovascular disease (IHD: RR 1.11, 95% CI [0.98, 1.27], 95% PI [0.46, 2.76] or cerebrovascular: RR 1.01, 95% CI [0.85, 1.21]) in women experiencing a miscarriage. Only women with a previous stillbirth were more likely to develop type 2 diabetes mellitus (T2DM) (RR: 1.16, 95% CI [1.07 to 2.26]; p < 0.001, 95% PI [1.05, 1.35]). Women with a stillbirth history had an increased risk of developing renal morbidities (RR 1.97, 95% CI [1.51, 2.57], p < 0.001, 95% [1.06, 4.72]) compared with controls. Women with a history of stillbirth had lower risk of breast cancer (RR: 0.80, 95% CI [0.67, 0.96], p-0.02, 95% PI [0.72, 0.93]). There was no evidence of altered risk of other malignancies in women experiencing pregnancy loss compared to controls. There was no evidence of long-term mental illness risk in women with previous pregnancy losses (stillbirth: RR 1.90, 95% CI [0.93, 3.88], 95% PI [0.34, 9.51], miscarriage: RR 1.78, 95% CI [0.88, 3.63], 95% PI [1.13, 4.16]). The main limitations include the potential for confounding due to use of aggregated data with variable degrees of adjustment. CONCLUSIONS: Our results suggest that women with a history of stillbirth have a greater risk of future cardiovascular disease, T2DM, and renal morbidities. Women experiencing miscarriages, single or multiple, do not seem to have an altered risk.

Estimating the value of future research into thromboprophylaxis for women during pregnancy and after delivery: a value of information analysis.

BACKGROUND: Risk assessment models (RAMs) are used to select women at increased risk of venous thromboembolism (VTE) during pregnancy and the puerperium for thromboprophylaxis. OBJECTIVES: To estimate the value of potential future studies that would reduce the decision uncertainty associated with offering thromboprophylaxis according to available RAMs in the following groups: high-risk antepartum women (eg, prior VTE), unselected postpartum women, and postpartum women with risk factors (obesity or cesarean delivery). METHODS: A decision-analytic model was developed to simulate clinical outcomes, lifetime costs, and quality-adjusted life-years for different thromboprophylaxis strategies, including thromboprophylaxis for all, thromboprophylaxis for none, and RAM-based thromboprophylaxis. The expected value of perfect information analysis was used to determine which factors are associated with high decision uncertainty. The value of future research studies was estimated using expected value of sample information analysis. Costs were assessed from a health and social services perspective. RESULTS: The expected value of perfect information analysis identified high decision uncertainty for high-risk antepartum women (£21.8 million) and obese postpartum women (£13.4 million), which was largely attributable to uncertainty regarding the effectiveness of thromboprophylaxis in reducing VTE. A randomized controlled trial of thromboprophylaxis compared with none in obese postpartum women is likely to have substantial value (£2.8 million; 300 participants per arm). A trial in women with previous VTE would have higher value but would be less acceptable. CONCLUSION: Future research should focus on estimating the effectiveness of thromboprophylaxis in obese postpartum women with additional risk factors who have not had a previous VTE.

A rapid landscape review of postpartum anaemia measurement: challenges and opportunities.

BACKGROUND: Anaemia is a reduction in haemoglobin concentration below a threshold, resulting from various factors including severe blood loss during and after childbirth. Symptoms of anaemia include fatigue and weakness, among others, affecting health and quality of life. Anaemic pregnant women have an increased risk of premature delivery, a low-birthweight infant, and postpartum depression. They are also more likely to have anaemia in the postpartum period which can lead to an ongoing condition and affect subsequent pregnancies. In 2019 nearly 37% of pregnant women globally had anaemia, and estimates suggest that 50-80% of postpartum women in low- and middle-income countries have anaemia, but currently there is no standard measurement or classification for postpartum anaemia. METHODS: A rapid landscape review was conducted to identify and characterize postpartum anaemia measurement searching references within three published systematic reviews of anaemia, including studies published between 2012 and 2021. We then conducted a new search for relevant literature from February 2021 to April 2022 in EMBASE and MEDLINE using a similar search strategy as used in the published reviews. RESULTS: In total, we identified 53 relevant studies. The timing of haemoglobin measurement ranged from within the immediate postpartum period to over 6 weeks. The thresholds used to diagnose anaemia in postpartum women varied considerably, with < 120, < 110, < 100 and < 80 g/L the most frequently reported. Other laboratory results frequently reported included ferritin and transferrin receptor. Clinical outcomes reported in 32 out of 53 studies included postpartum depression, quality of life, and fatigue. Haemoglobin measurements were performed in a laboratory, although it is unclear from the studies if venous samples and automatic analysers were used in all cases. CONCLUSIONS: This review demonstrates the need for improving postpartum anaemia measurement given the variability observed in published measures. With the high prevalence of anaemia, the relatively simple treatment for non-severe cases of iron deficiency anaemia, and its importance to public health with multi-generational effects, it is crucial to develop common measures for women in the postpartum period and promote rapid uptake and reporting.

Risk assessment models for venous thromboembolism in pregnancy and in the puerperium: a systematic review.

OBJECTIVES: To assess the comparative accuracy of risk assessment models (RAMs) to identify women during pregnancy and the early postnatal period who are at increased risk of venous thromboembolism (VTE). DESIGN: Systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. DATA SOURCES: MEDLINE, Embase, Cochrane Library and two research registers were searched until February 2021. ELIGIBILITY CRITERIA: All validation studies that examined the accuracy of a multivariable RAM (or scoring system) for predicting the risk of developing VTE in women who are pregnant or in the puerperium (within 6 weeks post-delivery). DATA EXTRACTION AND SYNTHESIS: Two authors independently selected and extracted data. Risk of bias was appraised using PROBAST (Prediction model Risk Of Bias ASsessment Tool). Data were synthesised without meta-analysis. RESULTS: Seventeen studies, comprising 19 externally validated RAMs and 1 internally validated model, met the inclusion criteria. The most widely evaluated RAMs were the Royal College of Obstetricians and Gynaecologists guidelines (six studies), American College of Obstetricians and Gynecologists guidelines (two studies), Swedish Society of Obstetrics and Gynecology guidelines (two studies) and the Lyon score (two studies). In general, estimates of sensitivity and specificity were highly variable with sensitivity estimates ranging from 0% to 100% for RAMs that were applied to antepartum women to predict antepartum or postpartum VTE and 0% to 100% for RAMs applied postpartum to predict postpartum VTE. Specificity estimates were similarly diverse ranging from 28% to 98% and 5% to 100%, respectively. CONCLUSIONS: Available data suggest that external validation studies have weak designs and limited generalisability, so estimates of prognostic accuracy are very uncertain. PROSPERO REGISTRATION NUMBER: CRD42020221094.

Deferred consent in emergency obstetric research: findings from qualitative interviews with women and recruiters in the ACROBAT pilot trial for severe postpartum haemorrhage.

OBJECTIVE: The ACROBAT pilot trial of early cryoprecipitate for severe postpartum haemorrhage used deferred consent procedures. Pretrial discussions with a patient and public involvement group found mixed views towards deferred consent. This study aimed to build an understanding of how the deferred consent procedures worked in practice, to inform plans for a full-scale trial. SETTING: Qualitative interview study within a cluster-randomised pilot trial, involving four London maternity services. PARTICIPANTS: Individual interviews were conducted postnatally with 10 women who had received blood transfusion for severe postpartum haemorrhage and had consented to the trial. We also interviewed four 'recruiters'-two research midwives and two clinical trials practitioners who conducted trial recruitment. RESULTS: Consent procedures in the ACROBAT pilot trial were generally acceptable and the intervention was viewed as low risk, but most women did not remember much about the consent conversation. As per trial protocol, recruiters sought to consent women before hospital discharge, but this time pressure had to be balanced against the need to ensure women were not approached when distressed or very unwell. Extra efforts had to be made to communicate trial information to women due to the exhaustion of their recovery and competing demands for their attention. Participant information was further complicated by explanations about the cluster design and change in transfusion process, even though the consent sought was for access to medical data. CONCLUSION: Our findings indicate that deferred consent procedures raise similar concerns as taking consent when emergency obstetric research is occurring-that is, the risk that participants may conflate research with clinical care, and that their ability to process trial information may be impacted by the stressful nature of recovery and newborn care. A future trial may support more meaningful informed consent by extending the window of consent discussion and ensuring trial information is minimal and easy to understand. TRIAL REGISTRATION NUMBER: ISRCTN12146519.

Myo-inositol nutritional supplement for prevention of gestational diabetes (EMmY): a randomised, placebo-controlled, double-blind pilot trial with nested qualitative study.

OBJECTIVES: To determine the feasibility and acceptability of conducting a randomised trial on the effects of myo-inositol in preventing gestational diabetes in high-risk pregnant women. DESIGN: A multicentre, double-blind, placebo-controlled, pilot randomised trial with nested qualitative evaluation. SETTING: Five inner city UK National Health Service hospitals PARTICIPANTS: Multiethnic pregnant women at 12+0 and 15+6 weeks' gestation with risk factors for gestational diabetes. INTERVENTIONS: 2 g of myo-inositol or placebo, both included 200 µg folic acid, twice daily until delivery. PRIMARY OUTCOME MEASURES: Rates of recruitment, randomisation, adherence and follow-up. SECONDARY OUTCOME MEASURES: Glycaemic indices (including homoeostatic model assessment-insulin resistance HOMA-IR), gestational diabetes (diagnosed using oral glucose tolerance test at 28 weeks and by delivery), maternal, perinatal outcomes, acceptability of intervention and costs. RESULTS: Of the 1326 women screened, 58% (773/1326) were potentially eligible, and 27% (205/773) were recruited. We randomised 97% (198/205) of all recruited women (99 each in intervention and placebo arms) and ascertained outcomes in 90% of women (178/198) by delivery. The mean adherence was 52% (SD 44) at 28 weeks' and 34% (SD 41) at 36 weeks' gestation. HOMA-IR and serum insulin levels were lower in the myo-inositol vs placebo arm (mean difference -0.6, 95% CI -1.2 to 0.0 and -2.69, 95% CI -5.26 to -0.18, respectively). The study procedures were acceptable to women and healthcare professionals. Women who perceived themselves at high risk of gestational diabetes were more likely to participate and adhere to the intervention. The powder form of myo-inositol and placebo, along with nausea in pregnancy were key barriers to adherence. CONCLUSIONS: A future trial on myo-inositol versus placebo to prevent gestational diabetes is feasible. The intervention will need to be delivered in a non-powder form to improve adherence. There is a signal for efficacy in reducing insulin resistance in pregnancy with myo-inositol. TRIAL REGISTRATION NUMBER: ISRCTN48872100.

Iron preparations for women of reproductive age with iron deficiency anaemia in pregnancy (FRIDA): a systematic review and network meta-analysis.

BACKGROUND: Numerous iron preparations are available for the treatment of iron deficiency anaemia in pregnancy. We aimed to provide a summary of the effectiveness and safety of iron preparations used in this setting. METHODS: We did a systematic review and network meta-analysis of randomised trials. We searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials, trial registers, and grey literature for trials published in any language from Jan 1, 2011, to Feb 28, 2021. We included trials including pregnant women with iron deficiency anaemia and evaluating iron preparations, irrespective of administration route, with at least 60 mg of elemental iron, in comparison with another iron or non-iron preparation. Three authors independently selected studies, extracted data, and did a risk of bias assessment using the Cochrane tool (version 1.0). The primary outcome was the effectiveness of iron preparations, evaluated by changes in haemoglobin concentration at 4 weeks from baseline. The secondary outcomes were change in serum ferritin concentration at 4 weeks from baseline and treatment-related severe and non-severe adverse events. We did random-effects pairwise and network meta-analyses. Side-effects were reported descriptively for each trial. This study is registered with PROSPERO, CRD42018100822. FINDINGS: Among 3037 records screened, 128 full-text articles were further assessed for eligibility. Of the 53 eligible trials (reporting on 9145 women), 30 (15 interventions; 3243 women) contributed data to the network meta-analysis for haemoglobin and 15 (nine interventions; 1396 women) for serum ferritin. The risk of bias varied across the trials contributing to network meta-analysis, with 22 of 30 trials in the network meta-analysis for haemoglobin judged to have a high or medium global risk of bias. Compared with oral ferrous sulfate, intravenous iron sucrose improved both haemoglobin (mean difference 7·17 g/L, 95% CI 2·62-11·73; seven trials) and serum ferritin (mean difference 49·66 µg/L, 13·63-85·69; four trials), and intravenous ferric carboxymaltose improved haemoglobin (mean difference 8·52 g/L, 0·51-16·53; one trial). The evidence for other interventions compared with ferrous sulfate was insufficient. The most common side-effects with oral iron preparations were gastrointestinal effects (nausea, vomiting, and altered bowel movements). Side-effects were less common with parenteral iron preparations, although these included local pain, skin irratation, and, on rare occasions, allergic reactions. INTERPRETATION: Iron preparations for treatment of iron deficiency anaemia in pregnancy vary in effectiveness, with good evidence of benefit for intravenous iron sucrose and some evidence for intravenous ferric carboxymaltose. Clinicians and policy makers should consider the effectiveness of individual preparations before administration, to ensure effective treatment. FUNDING: None.

COVID-19, thrombosis and pregnancy.

Increased thromboembolic events have been seen in patients hospitalised with COVID-19 pneumonia, especially those with acute respiratory distress syndrome requiring intensive care support. The coronavirus pandemic has had varied effects on pregnant women globally. Concerns about the potential for thromboembolic events in the prothrombotic period of pregnancy and puerperium when combined with COVID-19 infection, and the impact this may have on maternal and infant morbidity and mortality has led to the development of expert-led guidance providing increased use of thromboprophylaxis in this group. We discuss the impact of SARS-CoV-2 on national and international guidance to prevent thromboembolic events in pregnant women.

Effect of early cryoprecipitate transfusion versus standard care in women who develop severe postpartum haemorrhage (ACROBAT) in the UK: a protocol for a pilot cluster randomised trial.

INTRODUCTION: The incidence of severe postpartum haemorrhage (PPH) that requires blood transfusion is on the increase. Fibrinogen levels have been shown to drop early and significantly during PPH, which is associated with worse outcomes. Early fibrinogen replacement could potentially improve outcomes. No studies have investigated the clinical impact of early cryoprecipitate transfusion in PPH. Prior to performing a full-scale trial, a pilot study is needed to determine feasibility of the intervention and recruitment. METHODS: ACROBAT is a cluster-randomised pilot study with a qualitative evaluation. Four large London maternity units are randomised to either the intervention or control group. The intervention group will adapt their major obstetric haemorrhage procedures to administer cryoprecipitate early for primary PPH. The control group will retain their standard of care.We include women at >24 weeks gestation who are actively bleeding within 24 hours of delivery and for whom transfusion of red blood cells (RBCs) has been started. We exclude women who decline blood transfusions in advance or have inherited Factor XIII or fibrinogen deficiency. Due to the emergency nature of the intervention, informed consent for administering the intervention is waived.The primary objective is to assess the feasibility of administering cryoprecipitate within 90 min of RBC request, as compared with standard treatment where cryoprecipitate is given later or not at all. Secondary objectives include the feasibility of recruitment and data collection, reasons for and barriers to consent, preliminary maternal clinical outcomes, identification of the optimal infrastructure pathways for study delivery, and acceptability of the intervention and outcomes. ETHICS AND DISSEMINATION: The trial has approvals from the London-Brighton & Sussex Research Ethics Committee (ref. 18/LO/2062), the Confidentiality Advisory Group (ref. 18/CAG/0199) and Health Research Authority (IRAS number 237959). Data analysis and publication of manuscripts will start in Q3 2020. TRIAL REGISTRATION NUMBER: ISRCTN12146519.

Effectiveness and acceptability of metformin in preventing the onset of type 2 diabetes after gestational diabetes in postnatal women: a protocol for a randomised, placebo-controlled, double-blind feasibility trial­Optimising health outcomes with Metformin to prevent diAbetes After pregnancy (OMAhA).

INTRODUCTION: Up to half of all women diagnosed with gestational diabetes mellitus develop type 2 diabetes within 5 years after delivery. Metformin is effective in preventing type 2 diabetes in high-risk non-pregnant individuals, but its effect when commenced in the postnatal period is not known. We plan to assess the feasibility of evaluating metformin versus placebo in minimising the risk of dysglycaemia including type 2 diabetes after delivery in postnatal women with a history of gestational diabetes through a randomised trial. METHODS AND ANALYSIS: Optimising health outcomes with Metformin to prevent diAbetes After pregnancy (OMAhA) is a multicentre placebo-controlled double-blind randomised feasibility trial, where we will randomly allocate 160 postnatal women with gestational diabetes treated with medication to either metformin (intervention) or placebo (control) tablets to be taken until 1 year after delivery. The primary outcomes are rates of recruitment, randomisation, adherence and attrition. The secondary outcomes are maternal dysglycaemia, cost and quality of life outcomes in both arms, and acceptability of the study and intervention, which will be evaluated through a nested qualitative study. Feasibility outcomes will be summarised using descriptive statistics, point estimates and 95% CIs. ETHICS AND DISSEMINATION: The OMAhA study received ethics approval from the London-Brent Research Ethics Committee (18/LO/0505). Trial findings will be published in a peer-reviewed journal, disseminated at conferences, through our Patient and Public Involvement advisory group (Katie's Team) and through social media platforms. TRIAL REGISTRATION NUMBER: ISRCTN20930880.

Revisiting the basis for haemoglobin screening in pregnancy.

PURPOSE OF REVIEW: Anaemia affects up to 50% of pregnancies worldwide, and is associated with maternal and neonatal morbidity and mortality. Prevention and management of anaemia remains a priority. Despite this, there is ongoing debate on the optimal approach to identifying anaemia in pregnant women and the best strategies for prevention and management. The objective of this review is to describe the current landscape of haemoglobin testing in pregnancy in low and high-income countries. RECENT FINDINGS: Current definitions of anaemia in pregnancy comprise a laboratory threshold of haemoglobin below which treatment is offered. Haemoglobin measurement is not sensitive in detecting iron deficiency - the most common cause of maternal anaemia. Furthermore, these historical thresholds were derived from heterogeneous populations comprising men and women. Women with anaemia in pregnancy are offered iron therapy, without testing for the underlying cause. This may be appropriate in high-income settings, where iron deficiency is the likely cause, but may not address the complex causes of anaemia in other geographical areas. SUMMARY: Current thresholds of haemoglobin defining anaemia in pregnancy are under review. Further research and policy should focus on optimal strategies to identify women at risk of anaemia from all causes.

Reported Outcomes in Perinatal Iron Deficiency Anemia Trials: A Systematic Review.

BACKGROUND/AIMS: Iron deficiency (ID) and iron deficiency anemia (IDA) are global health concerns associated with adverse perinatal effects. Despite efforts taken at the international level, there is no consensus on unified prevention/treatment strategies, largely stemming from inconsistencies of outcome reporting. Our objective was to comprehensively assess outcome reporting perinatal iron intervention trials as Phase 1 of core outcome set (COS) development to inform future research. METHODS: Systematic search in MEDLINE, EMBASE, Cochrane Databases, and CINAHL (January 2000 - April 2016), with inclusion of trials involving pregnant or postpartum women with ID/IDA confirmed before recruitment. Articles were independently screened and selected by 2 reviewers; data were extracted in duplicate. Quality was assessed using published scoring systems. Outcome definitions and measurement methods were tabulated. RESULTS: Of 7,046 citations, 33 randomized controlled trials were included. Sixty-nine reported outcomes were categorized into 8 domains. High methodological quality characterized 25 (76%) studies. Reporting quality was low in 16 (49%), moderate in 13 (39%), and high in 4 (12%) studies. Variation was greatest for outcome definition, timing of assessment and measurement methods. CONCLUSION: This review identifies a comprehensive long-list of outcomes reported of perinatal iron interventions for ID/IDA. Beyond highlighting existing variation in outcome reporting, it provides a foundation for development of a COS for future trials.

Effectiveness and acceptability of myo-inositol nutritional supplement in the prevention of gestational diabetes (EMmY): a protocol for a randomised, placebo-controlled, double-blind pilot trial.

INTRODUCTION: Gestational diabetes increases maternal and offspring complications in pregnancy and cardiovascular complications in the long term. The nutritional supplement myo-inositol may prevent gestational diabetes; however, further evaluation is required, especially in multiethnic high-risk mothers. Our pilot trial on myo-inositol to prevent gestational diabetes will evaluate trial processes, assess acceptability to mothers and obtain preliminary estimates of effect and cost data prior to a large full-scale trial. METHODS AND ANALYSIS: EMmY is a multicentre, placebo-controlled, double-blind, pilot, randomised trial, with qualitative evaluation. We will recruit pregnant women at 12-15+6 weeks' gestation, with gestational diabetes risk factors, from five maternity units in England between 2018 and 2019. We will randomise 200 women to take either 2 g of myo-inositol powder (intervention) or placebo, twice daily until delivery. We will assess rates of recruitment, randomisation, adherence to intervention and follow-up. Gestational diabetes will be diagnosed at 24-28 weeks as per the National Institute for Health and Care Excellence (NICE) criteria (fasting plasma glucose: ≥5.6 mmol/L and 2-hour plasma glucose: ≥7.8 mmol/L). We will assess the effects of myo-inositol on glycaemic indices at 28 weeks and on other maternal, fetal and neonatal outcomes at postnatal discharge. Qualitative evaluation will explore the acceptability of the trial and the intervention among women and healthcare professionals. Cost data and health-related quality of life measures will be captured. We will summarise feasibility outcomes using standard methods for proportions and other descriptive statistics, and where appropriate, report point estimates of effect sizes (eg, mean differences and relative risks) and associated 95% CIs. ETHICS AND DISSEMINATION: Ethical approval was obtained through the London Queen Square Research Ethics Committee (17/LO/1741). Study findings will be submitted for publication in peer-reviewed journals. Newsletters will be made available to participants, healthcare professionals and members of Katie's Team (a patient and public advisory group) to disseminate. TRIAL REGISTRATION NUMBER: ISRCTN48872100. PROTOCOL VERSION AND DATE: Version 4.0, 15 January 2018.

Risk of maternal mortality in women with severe anaemia during pregnancy and post partum: a multilevel analysis.

BACKGROUND: Anaemia affects as many as half of all pregnant women in low-income and middle-income countries, but the burden of disease and associated maternal mortality are not robustly quantified. We aimed to assess the association between severe anaemia and maternal death with data from the WHO Multicountry Survey on maternal and newborn health. METHODS: We used multilevel and propensity score regression analyses to establish the relation between severe anaemia and maternal death in 359 health facilities in 29 countries across Latin America, Africa, the Western Pacific, eastern Mediterranean, and southeast Asia. Severe anaemia was defined as antenatal or postnatal haemoglobin concentrations of less than 70 g/L in a blood sample obtained before death. Maternal death was defined as death any time after admission until the seventh day post partum or discharge. In regression analyses, we adjusted for post-partum haemorrhage, general anaesthesia, admission to intensive care, sepsis, pre-eclampsia or eclampsia, thrombocytopenia, shock, massive transfusion, severe oliguria, failure to form clots, and severe acidosis as confounding variables. These variables were used to develop the propensity score. FINDINGS: 312 281 women admitted in labour or with ectopic pregnancies were included in the adjusted multilevel logistic analysis, and 12 470 were included in the propensity score regression analysis. The adjusted odds ratio for maternal death in women with severe anaemia compared with those without severe anaemia was 2·36 (95% CI 1·60-3·48). In the propensity score analysis, severe anaemia was also associated with maternal death (adjusted odds ratio 1·86 [95% CI 1·39-2·49]). INTERPRETATION: Prevention and treatment of anaemia during pregnancy and post partum should remain a global public health and research priority. FUNDING: Barts and the London Charity.

Accuracy of fetal fibronectin for assessing preterm birth risk in asymptomatic pregnant women: a systematic review and meta-analysis.

INTRODUCTION: Fetal fibronectin (fFN) is a validated test for assessing risk of preterm birth for women presenting with symptoms. Our aim was to evaluate the accuracy of fFN to detect the risk of preterm birth in asymptomatic women. MATERIAL AND METHODS: Searches were conducted to identify studies where fFN was performed in asymptomatic women beyond 22 weeks' gestation. EMBASE, MEDLINE, CINHAL, AMED and BNI were searched between 2005 and 2017. Studies before 2005 were identified from a published systematic review. Women were grouped as singleton pregnancies, with and without risk factors for preterm birth, and multiple pregnancy. Quality assessment was performed using QUADAS-2. When possible, data were pooled using a hierarchical, bivariate random effects model. RESULTS: Fifteen studies met the inclusion criteria: six studies of singleton pregnancies in women without risk factors (1236 women), four in women with risk factors for preterm birth (2628 women) and five studies were of multiple pregnancy (1427 women). The pooled sensitivity and specificity of fFN in "no risk factors singletons" were 0.48 (95% CI 0.20-0.77), and 0.96 (95% CI 0.86-0.99), respectively. The likelihood ratio of a positive test result was 12 (95% CI 4.70-30.68). The pooled sensitivity and specificity of fFN in "risk factors singletons" were 0.34 (95% CI 0.24-0.43), and 0.91 (95% CI 0.88-0.93). The accuracy of fFN in multiple pregnancies was inconclusive. CONCLUSION: Our findings suggest in asymptomatic singleton pregnancies without risk factors, a positive fFN result indicates a large shift from pre- to post-test probability, possibly identifying women at increased risk of preterm birth.

Serum ferritin as an indicator of iron status: what do we need to know?

Determination of iron status in pregnancy and in young children is essential for both clinical and public health practice. Clinical diagnosis of iron deficiency (ID) through sampling of bone marrow to identify the absence of body iron stores is impractical in most cases. Serum ferritin (SF) concentrations are the most commonly deployed indicator for determining ID, and low SF concentrations reflect a state of iron depletion. However, there is considerable variation in SF cutoffs recommended by different expert groups to diagnose ID. Moreover, the cutoffs used in different clinical laboratories are heterogeneous. There are few studies of diagnostic test accuracy to establish the sensitivity and specificity of SF compared with key gold standards (such as absent bone marrow iron stores, increased intestinal iron absorption, and hemoglobin response to SF) among noninflamed, outpatient populations. The limited data available suggest the commonly recommended SF cutoff of <15 µg/L is a specific but not sensitive cutoff, although evidence is limited. Data from women during pregnancy or from young children are especially uncommon. Most data are from studies conducted >30 y ago, do not reflect ethnic or geographic diversity, and were performed in an era for which laboratory methods no longer reflect present practice. Future studies to define the appropriate SF cutoffs are urgently needed and would also provide an opportunity to compare this indicator with other established and emerging iron indexes. In addition, future work would benefit from a focus on elucidating cutoffs and indexes relevant to iron adequacy.