Preeclampsia Prevention Using Routine Versus Screening Test-Indicated Aspirin in Low-Risk Women

Benefits and harms of antenatal and newborn screening programmes in health economic assessments: the VALENTIA systematic review and qualitative investigation

Background

Health economic assessments are used to determine whether the resources needed to generate net benefit from an antenatal or newborn screening programme, driven by multiple benefits and harms, are justifiable. It is not known what benefits and harms have been adopted by economic evaluations assessing these programmes and whether they omit benefits and harms considered important to relevant stakeholders.

Objectives

(1) To identify the benefits and harms adopted by health economic assessments in this area, and to assess how they have been measured and valued; (2) to identify attributes or relevance to stakeholders that ought to be considered in future economic assessments; and (3) to make recommendations about the benefits and harms that should be considered by these studies.

Design

Mixed methods combining systematic review and qualitative work.

Systematic review methods

We searched the published and grey literature from January 2000 to January 2021 using all major electronic databases. Economic evaluations of an antenatal or newborn screening programme in one or more Organisation for Economic Co-operation and Development countries were considered eligible. Reporting quality was assessed using the Consolidated Health Economic Evaluation Reporting Standards checklist. We identified benefits and harms using an integrative descriptive analysis and constructed a thematic framework.

Qualitative methods

We conducted a meta-ethnography of the existing literature on newborn screening experiences, a secondary analysis of existing individual interviews related to antenatal or newborn screening or living with screened-for conditions, and a thematic analysis of primary data collected with stakeholders about their experiences with screening.

Results

The literature searches identified 52,244 articles and reports, and 336 unique studies were included. Thematic framework resulted in seven themes: (1) diagnosis of screened for condition, (2) life-years and health status adjustments, (3) treatment, (4) long-term costs, (5) overdiagnosis, (6) pregnancy loss and (7) spillover effects on family members. Diagnosis of screened-for condition (115, 47.5%), life-years and health status adjustments (90, 37.2%) and treatment (88, 36.4%) accounted for most of the benefits and harms evaluating antenatal screening. The same themes accounted for most of the benefits and harms included in studies assessing newborn screening. Long-term costs, overdiagnosis and spillover effects tended to be ignored. The wide-reaching family implications of screening were considered important to stakeholders. We observed good overlap between the thematic framework and the qualitative evidence.

Limitations

Dual data extraction within the systematic literature review was not feasible due to the large number of studies included. It was difficult to recruit healthcare professionals in the stakeholder's interviews.

Conclusions

There is no consistency in the selection of benefits and harms used in health economic assessments in this area, suggesting that additional methods guidance is needed. Our proposed thematic framework can be used to guide the development of future health economic assessments evaluating antenatal and newborn screening programmes.

Study registration

This study is registered as PROSPERO CRD42020165236.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR127489) and is published in full in Health Technology Assessment; Vol. 28, No. 25. See the NIHR Funding and Awards website for further award information.

Low-dose aspirin for the prevention of preterm birth in nulliparous women: systematic review and meta-analysis

OBJECTIVE

The objective was to assess the efficacy and safety of low-dose aspirin for the prevention of preterm birth in nulliparous women.

DATA SOURCES

We searched PubMed, Embase and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception to June 2022.

STUDY ELIGIBILITY CRITERIA

Randomized controlled trials that compared aspirin to placebo in nulliparous women were eligible.

METHODS

This study was reported in accordance with the PRISMA 2020 checklist. The primary outcomes of this study were the rates of preterm birth at less than 37 weeks and less than 34 weeks of gestation. The secondary outcomes included postpartum hemorrhage, placental abruption, cesarean section, any hypertensive disorder of pregnancy and small for gestational age. Relative risks with their 95% confidence intervals were calculated for analysis. Heterogeneity was assessed by Cochran's Q test and Higgins's I2. A random-effects model was used when I2 was > 50% to generate the RR and 95% CI; otherwise, a fixed-effects model was used. The risk of publication bias was assessed by funnel plots. We performed sensitivity analysis by sequentially omitting each included study to confirm the robustness of the analysis.

RESULTS

Seven studies with a total of 29,029 participants were included in this review. Six studies were assessed as having a low risk of bias or an unclear risk of bias, and one study was judged as having a high risk of bias. In nulliparous women, low-dose aspirin was associated with a significant reduction in the rate of preterm birth at less than 34 weeks of gestational age (RR 0.84,95% CI: 0.71-0.99; I2 = 0%; P = 0.04), but we did not observe a significant difference in the rate of preterm birth at less than 37 weeks of gestation (RR 0.96,95% CI: 0.90-1.02; I2 = 31%; P = 0.18). Low-dose aspirin was associated with a significant increase in the rates of postpartum hemorrhage (RR 1.32,95% CI: 1.14-1.54; I2 = 0%; P = 0.0003), placental abruption (RR 2.18,95% CI: 1.10-4.32; I2 = 16%; P = 0.02) and cesarean section (RR 1.053, 95% CI: 1.001-1.108; I2 = 0%; P = 0.05) in nulliparous women. We also did not observe a significant effect of low-dose aspirin on the rates of any hypertensive disorder of pregnancy (RR 1.05, 95% CI: 0.96-1.14; I2 = 9%; P = 0.28) or small for gestational age (RR 0.96, 95% CI: 0.91-1.02; I2 = 0%; P = 0.16) in nulliparous women. Funnel plots indicated that no significant publication bias existed in this meta-analysis. Except for preterm birth at less than 34 weeks of gestation, placental abruption and cesarean section, the sensitivity analysis showed similar results, which confirmed the robustness of this meta-analysis.

CONCLUSIONS

Low-dose aspirin might reduce the risk of preterm birth at less than 34 weeks of gestation in nulliparous women. The use of low-dose aspirin in nulliparous women increased the risk of postpartum hemorrhage and might increase the risk of placental abruption and cesarean section.

The IRELAnD study-investigating the role of early low-dose aspirin in diabetes mellitus: a double-blinded, placebo-controlled, randomized trial

BACKGROUND

Although aspirin therapy is being increasingly advocated with the intention of risk modification for a wide range of pregnancy complications, women with prepregnancy diabetes mellitus are commonly excluded from clinical trials.

OBJECTIVE

The primary aim of this study was to examine the effect of aspirin therapy on a composite measure of adverse perinatal outcome in pregnancies complicated by pregestational diabetes mellitus.

STUDY DESIGN

A double-blinded, placebo-controlled randomized trial was conducted at 6 university-affiliated perinatology centers. Women with type 1 diabetes mellitus or type 2 diabetes mellitus of at least 6 months' duration were randomly allocated to 150-mg daily aspirin or placebo from 11 to 14 weeks' gestation until 36 weeks. Established vascular complications of diabetes mellitus, including chronic hypertension or nephropathy, led to exclusion from the trial. The primary outcome was a composite measure of placental dysfunction (preeclampsia, fetal growth restriction, preterm birth <34 weeks' gestation, or perinatal mortality). The planned sample size was 566 participants to achieve a 35% reduction in the primary outcome, assuming 80% statistical power. Secondary end points included maternal and neonatal outcomes and determination of insulin requirements across gestation. Data were centrally managed using ClinInfo and analyzed using SAS 9.4. The 2 treatment groups were compared using t tests or chi-square tests, as required, and longitudinal data were compared using a repeated-measures analysis.

RESULTS

From February 2020 to September 2022, 191 patients were deemed eligible, 134 of whom were enrolled (67 randomized to aspirin and 67 to placebo) with a retrospective power of 64%. A total of 101 (80%) women had type 1 diabetes mellitus and 25 (20%) had type 2 diabetes mellitus. Reaching the target sample size was limited by the impact of the COVID-19 pandemic. Baseline characteristics were similar between the aspirin and placebo groups. Treatment compliance was very high and similar between groups (97% for aspirin, 94% for placebo). The risk of the composite measure of placental dysfunction did not differ between groups (25% aspirin vs 21% placebo; P=.796). Women in the aspirin group had significantly lower insulin requirements throughout pregnancy compared with the placebo group. Insulin requirements in the aspirin group increased on average from 0.7 units/kg at baseline to 1.1 units/kg by 36 weeks' gestation (an average 83% within-patient increase), and increased from 0.7 units/kg to 1.3 units/kg (a 181% within-patient increase) in the placebo group, over the same gestational period (P=.002). Serial hemoglobin A1c levels were lower in the aspirin group than in the placebo group, although this trend did not reach statistical significance.

CONCLUSION

In this multicenter, double-blinded, placebo-controlled randomized trial, aspirin did not reduce the risk of adverse perinatal outcome in pregnancies complicated by prepregnancy diabetes mellitus. Compared with the placebo group, aspirin-treated patients required significantly less insulin throughout pregnancy, indicating a beneficial effect of aspirin on glycemic control. Aspirin may exert a plausible placenta-mediated effect on pregestational diabetes mellitus that is not limited to its antithrombotic properties.

First trimester screening for pre-eclampsia and targeted aspirin prophylaxis: a cost-effectiveness cohort study

OBJECTIVE

Investigate cost-effectiveness of first trimester pre-eclampsia screening using the Fetal Medicine Foundation (FMF) algorithm and targeted aspirin prophylaxis in comparison with standard care.

DESIGN

Retrospective observational study.

SETTING

London tertiary hospital.

POPULATION

5957 pregnancies screened for pre-eclampsia using the National Institute for Health and Care Excellence (NICE) method.

METHODS

Differences in pregnancy outcomes between those who developed pre-eclampsia, term pre-eclampsia and preterm pre-eclampsia were compared by the Kruskal-Wallis and Chi-square tests. The FMF algorithm was applied retrospectively to the cohort. A decision analytic model was used to estimate costs and outcomes for pregnancies screened using NICE and those screened using the FMF algorithm. The decision point probabilities were calculated using the included cohort.

MAIN OUTCOME MEASURES

Incremental healthcare costs and QALY gained per pregnancy screened.

RESULTS

Of 5957 pregnancies, 12.8% and 15.9% were screen-positive for development of pre-eclampsia using the NICE and FMF methods, respectively. Of those who were screen-positive by NICE recommendations, aspirin was not prescribed in 25%. Across the three groups, namely, pregnancies without pre-eclampsia, term pre-eclampsia and preterm pre-eclampsia there was a statistically significant trend in rates of emergency caesarean (respectively 21%, 43% and 71.4%; P < 0.001), admission to neonatal intensive care unit (NICU) (5.9%, 9.4%, 41%; P < 0.001) and length of stay in NICU. The FMF algorithm was associated with seven fewer cases of preterm pre-eclampsia, cost saving of £9.06 and QALY gain of 0.00006/pregnancy screened.

CONCLUSIONS

Using a conservative approach, application of the FMF algorithm achieved clinical benefit and an economic cost saving.

Aspirin in Pregnancy

Preeclampsia is associated with significant perinatal morbidity and mortality. Aspirin has been long purported and extensively studied for prevention of preeclampsia. For this reason, the U.S. Preventive Services Task Force, the American College of Obstetricians and Gynecologists, and the Society for Maternal-Fetal Medicine recommend its use in pregnancy for preeclampsia prevention in those at high risk. Yet, much controversy exists regarding optimal use in pregnancy with guidelines across global organizations varying. In this narrative review, we summarize the published literature related to the safety, optimal dose, and timing and duration of use of aspirin, as well as other indications for which aspirin has been studied in pregnancy.

The Role of Acetylsalicylic Acid in the Prevention of Pre-Eclampsia, Fetal Growth Restriction, and Preterm Birth

BACKGROUND

Recent studies suggest that low-dose acetylsalicylic acid (ASA) can lower pregnancy-associated morbidity.

METHODS

This review is based on pertinent publications that were retrieved by a selective search in PubMed, with special attention to systematic reviews, metaanalyses, and randomized controlled trials.

RESULTS

Current meta-analyses document a reduction of the risk of the occurrence of pre-eclampsia (RR 0.85, NNT 50), as well as beneficial effects on the rates of preterm birth (RR 0.80, NNT 37), fetal growth restriction (RR 0.82, NNT 77), and perinatal death (RR 0.79, NNT 167). Moreover, there is evidence that ASA raises the rate of live births after a prior spontaneous abortion, while also lowering the rate of spontaneous preterm births (RR 0.89, NNT 67). The prerequisites for therapeutic success are an adequate ASA dose, early initiation of ASA, and the identification of women at risk of pregnancy-associated morbidity. Side effects of treatment with ASA in this patient group are rare and mainly involve bleeding in connection with the pregnancy (RR 0.87, NNH 200).

CONCLUSION

ASA use during pregnancy has benefits beyond reducing the risk of pre-eclampsia. The indications for taking ASA during pregnancy may be extended at some point in the future; at present, in view of the available evidence, it is still restricted to high-risk pregnancies.

Which first-trimester risk assessment method for preeclampsia is most suitable? A model-based impact study

BACKGROUND

Low-dose aspirin treatment reduces the risk of preeclampsia among high-risk pregnant women. Internationally, several first-trimester risk-calculation methods are applied.

OBJECTIVE

This study aimed to assess the costs and benefits of different first-trimester preeclampsia risk estimation algorithms: EXPECT (an algorithmic prediction model based on maternal characteristics), National Institute for Health and Care Excellence (a checklist of risk factors), and the Fetal Medicine Foundation (a prediction model using additional uterine artery Doppler measurement and laboratory testing) models, coupled with low-dose aspirin treatment, in comparison with no risk assessment.

STUDY DESIGN

We constructed a decision analytical model estimating the number of cases of preeclampsia with each strategy and the costs of risk assessment for preeclampsia and early aspirin treatment, expressed in euros (€) in a hypothetical population of 100,000 women. We performed 1-way sensitivity analyses to assess the impact of adherence rates on model outcomes.

RESULTS

Application of the EXPECT, National Institute for Health and Care Excellence, and Fetal Medicine Foundation models results in respectively 1.98%, 2.55%, and 1.90% of the women developing preeclampsia, as opposed to 3.00% of women in the case of no risk assessment. Overall, the net financial benefits of the EXPECT, National Institute for Health and Care Excellence, and Fetal Medicine Foundation models relative to no risk assessment are €144, €43, and €38 per patient, respectively. The respective percentages of women receiving aspirin treatment are 18.6%, 10.2%, and 6.0% for the 3 risk assessment methods.

CONCLUSION

The EXPECT and Fetal Medicine Foundation model are comparable with regard to numbers of prevented preeclampsia cases, and both are superior to the National Institute for Health and Care Excellence model and to no risk assessment. EXPECT is less resource-demanding and results in the highest cost savings, but also requires the highest number of women to be treated with aspirin. When deciding which strategy is preferable, cost savings and easier use have to be weighed against the degree of overtreatment, although low-dose aspirin has no clear disadvantages during pregnancy.

Directive clinique no 426 : Troubles hypertensifs de la grossesse : Diagnostic, prédiction, prévention et prise en charge

OBJECTIF

La présente directive a été élaborée par des fournisseurs de soins de maternité en obstétrique et en médecine interne. Elle aborde le diagnostic, l'évaluation et la prise en charge des troubles hypertensifs de la grossesse, la prédiction et la prévention de la prééclampsie ainsi que les soins post-partum des femmes avec antécédent de trouble hypertensif de la grossesse.

POPULATION CIBLE

Femmes enceintes. BéNéFICES, RISQUES ET COûTS: La mise en œuvre des recommandations de la présente directive devrait réduire l'incidence des troubles hypertensifs de la grossesse, en particulier la prééclampsie, et des issues défavorables associées. DONNéES PROBANTES: La revue exhaustive de la littérature a été mise à jour en tenant compte des nouvelles données probantes jusqu'en décembre 2020 et en suivant la même méthodologie que pour la précédente directive de la Société des obstétriciens et gynécologues du Canada (SOGC) sur les troubles hypertensifs de la grossesse. La recherche s'est limitée aux articles publiés en anglais ou en français. Les recommandations relatives aux traitements s'appuient d'abord sur les essais cliniques randomisés et les revues systématiques (lorsque disponibles), ainsi que sur l'évaluation des résultats cliniques substantiels chez les mères et les bébés. MéTHODES DE VALIDATION: Les auteurs se sont entendus sur le contenu et les recommandations par consensus et ont répondu à l'examen par les pairs du comité de médecine fœto-maternelle de la SOGC. Les auteurs ont évalué la qualité des données probantes et la force des recommandations en utilisant le cadre méthodologique d'évaluation, de développement et d'évaluation (GRADE) et se sont gardé l'option de désigner certaines recommandations par la mention « bonne pratique ». Voir l'annexe A en ligne (tableau A1 pour les définitions et tableau A2 pour l'interprétation des recommandations fortes et conditionnelles [faibles]). Le conseil d'administration de la SOGC a approuvé la version définitive aux fins de publication.

PROFESSIONNELS CIBLES

Tous les fournisseurs de soins de santé (obstétriciens, médecins de famille, sages-femmes, infirmières et anesthésistes) qui prodiguent des soins aux femmes avant, pendant ou après la grossesse.

RECOMMANDATIONS

Guideline No. 426: Hypertensive Disorders of Pregnancy: Diagnosis, Prediction, Prevention, and Management

OBJECTIVE

This guideline was developed by maternity care providers from obstetrics and internal medicine. It reviews the diagnosis, evaluation, and management of the hypertensive disorders of pregnancy (HDPs), the prediction and prevention of preeclampsia, and the postpartum care of women with a previous HDP.

TARGET POPULATION

Pregnant women.

BENEFITS, HARMS, AND COSTS

Implementation of the recommendations in these guidelines may reduce the incidence of the HDPs, particularly preeclampsia, and associated adverse outcomes.

EVIDENCE

A comprehensive literature review was updated to December 2020, following the same methods as for previous Society of Obstetricians and Gynaecologists of Canada (SOGC) HDP guidelines, and references were restricted to English or French. To support recommendations for therapies, we prioritized randomized controlled trials and systematic reviews (if available), and evaluated substantive clinical outcomes for mothers and babies.

VALIDATION METHODS

The authors agreed on the content and recommendations through consensus and responded to peer review by the SOGC Maternal Fetal Medicine Committee. The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, along with the option of designating a recommendation as a "good practice point." See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional [weak] recommendations).The Board of the SOGC approved the final draft for publication.

INTENDED USERS

All health care providers (obstetricians, family doctors, midwives, nurses, and anesthesiologists) who provide care to women before, during, or after pregnancy.

RECOMMENDATIONS

Toward personalized management of chronic hypertension in pregnancy

Chronic hypertension complicates 1% to 2% of pregnancies, and it is increasingly common. Women with chronic hypertension are an easily recognized group who are in touch with a wide variety of healthcare providers before, during, and after pregnancy, mandating that chronic hypertension in pregnancy be within the scope of many practitioners. We reviewed recent data on management to inform current care and future research. This study is a narrative review of published literature. Compared with normotensive women, women with chronic hypertension are at an increased risk of maternal and perinatal complications. Women with chronic hypertension who wish to be involved in their care can do by measuring blood pressure at home. Accurate devices for home blood pressure monitoring are now readily available. The diagnostic criteria for superimposed preeclampsia remain problematic because most guidelines continue to include deteriorating blood pressure control in the definition. It has not been established how angiogenic markers may aid in confirmation of the diagnosis of superimposed preeclampsia when suspected, over and above information provided by routinely available clinical data and laboratory results. Although chronic hypertension is a strong risk factor for preeclampsia, and aspirin decreases preeclampsia risk, the effectiveness specifically among women with chronic hypertension has been questioned. It is unclear whether calcium has an independent effect in preeclampsia prevention in such women. Treating hypertension with antihypertensive therapy halves the risk of progression to severe hypertension, thrombocytopenia, and elevated liver enzymes, but a reduction in preeclampsia or serious maternal complications has not been observed; however, the lack of evidence for the latter is possibly owing to few events. In addition, treating chronic hypertension neither reduces nor increases fetal or newborn death or morbidity, regardless of the gestational age at which the antihypertensive treatment is started. Antihypertensive agents are not teratogenic, but there may be an increase in malformations associated with chronic hypertension itself. At present, blood pressure treatment targets used in clinics are the same as those used at home, although blood pressure values tend to be inconsistently lower at home among women with hypertension. Although starting all women on the same antihypertensive medication is usually effective in reducing blood pressure, it remains unclear whether there is an optimal agent for such an approach or how best to use combinations of antihypertensive medications. An alternative approach is to individualize care, using maternal characteristics and blood pressure features beyond blood pressure level (eg, variability) that are of prognostic value. Outcomes may be improved by timed birth between 38 0/7 and 39 6/7 weeks' gestation based on observational literature; of note, confirmatory trial evidence is pending. Postnatal care is facilitated by the acceptability of most antihypertensives (including angiotensin-converting enzymes inhibitors) for use in breastfeeding. The evidence base to guide the care of pregnant women with chronic hypertension is growing and aligning with international guidelines. Addressing outstanding research questions would inform personalized care of chronic hypertension in pregnancy.

Prevention of preeclampsia with aspirin

Preeclampsia is defined as hypertension arising after 20 weeks of gestational age with proteinuria or other signs of end-organ damage and is an important cause of maternal and perinatal morbidity and mortality, particularly when of early onset. Although a significant amount of research has been dedicated in identifying preventive measures for preeclampsia, the incidence of the condition has been relatively unchanged in the last decades. This could be attributed to the fact that the underlying pathophysiology of preeclampsia is not entirely understood. There is increasing evidence suggesting that suboptimal trophoblastic invasion leads to an imbalance of angiogenic and antiangiogenic proteins, ultimately causing widespread inflammation and endothelial damage, increased platelet aggregation, and thrombotic events with placental infarcts. Aspirin at doses below 300 mg selectively and irreversibly inactivates the cyclooxygenase-1 enzyme, suppressing the production of prostaglandins and thromboxane and inhibiting inflammation and platelet aggregation. Such an effect has led to the hypothesis that aspirin could be useful for preventing preeclampsia. The first possible link between the use of aspirin and the prevention of preeclampsia was suggested by a case report published in 1978, followed by the first randomized controlled trial published in 1985. Since then, numerous randomized trials have been published, reporting the safety of the use of aspirin in pregnancy and the inconsistent effects of aspirin on the rates of preeclampsia. These inconsistencies, however, can be largely explained by a high degree of heterogeneity regarding the selection of trial participants, baseline risk of the included women, dosage of aspirin, gestational age of prophylaxis initiation, and preeclampsia definition. An individual patient data meta-analysis has indicated a modest 10% reduction in preeclampsia rates with the use of aspirin, but later meta-analyses of aggregate data have revealed a dose-response effect of aspirin on preeclampsia rates, which is maximized when the medication is initiated before 16 weeks of gestational age. Recently, the Aspirin for Evidence-Based Preeclampsia Prevention trial has revealed that aspirin at a daily dosage of 150 mg, initiated before 16 weeks of gestational age, and given at night to a high-risk population, identified by a combined first trimester screening test, reduces the incidence of preterm preeclampsia by 62%. A secondary analysis of the Aspirin for Evidence-Based Preeclampsia Prevention trial data also indicated a reduction in the length of stay in the neonatal intensive care unit by 68% compared with placebo, mainly because of a reduction in births before 32 weeks of gestational age with preeclampsia. The beneficial effect of aspirin has been found to be similar in subgroups according to different maternal characteristics, except for the presence of chronic hypertension, where no beneficial effect is evident. In addition, the effect size of aspirin has been found to be more pronounced in women with good compliance to treatment. In general, randomized trials are underpowered to investigate the treatment effect of aspirin on the rates of other placental-associated adverse outcomes such as fetal growth restriction and stillbirth. This article summarizes the evidence around aspirin for the prevention of preeclampsia and its complications.

Prospective evaluation of first-trimester screening strategy for preterm pre-eclampsia and its clinical applicability in China

OBJECTIVES

To evaluate, in a Chinese population, the performance of a screening strategy for preterm pre-eclampsia (PE) using The Fetal Medicine Foundation (FMF)'s competing-risks model and to explore its clinical applicability in mainland China.

METHODS

This was a prospective, multicenter, observational cohort study including 10 899 women with singleton pregnancy who sought prenatal care at one of 13 hospitals, located in seven cities in mainland China, between 1 December 2017 and 30 December 2019. Mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI) and maternal serum levels of placental growth factor (PlGF) and pregnancy-associated plasma protein-A (PAPP-A) at 11 + 0 to 13 + 6 weeks' gestation were measured and converted into multiples of the median using Chinese reference ranges. Individualized risk for preterm PE was calculated using the FMF algorithm. Prior risk was calculated based on maternal demographic characteristics and obstetric history. We evaluated the efficiency of the screening strategy using various combinations of biomarkers and analyzed its predictive performance for a composite of placenta-associated adverse pregnancy outcomes, including PE, placental abruption, small-for-gestational age (SGA) and preterm birth, at fixed false-positive rates for preterm PE.

RESULTS

We identified 312 pregnancies that developed PE, of which 117 cases were diagnosed as preterm PE (< 37 weeks' gestation). There were 386 pregnancies complicated by severe composite placenta-associated adverse outcome, including preterm PE, 146 cases of severe SGA (birth weight < 3^rd percentile) neonate, 61 cases with placental abruption and 109 cases of early preterm birth < 34 gestational weeks. The triple-marker model containing biomarkers MAP, UtA-PI and PAPP-A achieved, at fixed false-positive rates of 10%, 15% and 20%, detection rates for preterm PE of 65.0%, 72.7% and 76.1%, respectively, and detection rates for severe composite placenta-associated adverse outcome of 34.7%, 41.7% and 46.4%, respectively. Replacing PAPP-A with PlGF or adding PlGF to the model did not improve the performance. Of women screening positive for preterm PE at a fixed 5% false-positive rate, an estimated 30% developed at least one placenta-associated adverse pregnancy outcome, including PE, placental abruption, SGA (birth weight < 10^th percentile) and preterm birth < 37 weeks.

CONCLUSIONS

The FMF competing-risks model for preterm PE was found to be effective in screening a mainland Chinese population. Women who screened positive for preterm PE had increased risk for other placenta-associated pregnancy complications. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Cost-utility of a first-trimester screening strategy versus the standard of care for nulliparous women to prevent pre-term pre-eclampsia in Belgium

OBJECTIVES

To assess the cost-effectiveness of the Fetal Medicine Foundation (FMF) combined first-trimester pre-eclampsia (PE) screening algorithm, coupled with low-dose aspirin treatment in high-risk patients, compared to the standard of care (SOC; screening based on maternal risk factors) for nulliparous pregnancies in Belgium.

STUDY DESIGN

A decision analytic model was used to estimate the costs and outcomes for patients screened using the SOC and for those using the FMF screening algorithm, from the Belgian payers' perspective. Where possible, the probabilities and associated costs at each decision point were calculated based on published literature and public databases.

MAIN OUTCOME MEASURES

Cost-effectiveness was assessed using an incremental cost-effectiveness ratio. One-way sensitivity analyses were performed to assess the impact of independent variations in each model parameter. A probabilistic sensitivity analysis was used to estimate the impact of the overall uncertainty of the model on the estimated cost-effectiveness.

RESULTS

Considering an estimated 51,309 pregnancies in nulliparous women in Belgium per year, the FMF screening algorithm resulted in fewer cases of pre-term PE compared with the SOC (479 versus 816 cases) and a cost saving of €28.67 per patient. The outcome in quality-adjusted life-years was similar for both screening approaches (FMF screening algorithm 1.8521 versus SOC 1.8518). The FMF screening algorithm was cost-saving and more effective in 99.4% of simulations.

CONCLUSIONS

The FMF screening algorithm coupled with early intervention using low-dose aspirin has the potential to prevent an additional 337 cases of pre-term PE per year compared with the current SOC in this population, along with a cost saving.

Maternal adipose tissue to early preeclampsia risk detection: Is the time to maternal ultrasound beyond fetal evaluation?

INTRODUCTION

This study aims to determine the predictive capacity of isolated maternal periumbilical and epigastric fat measurements during pregnancy to hypertensive outcomes.

METHODS

A cohort study was conducted with pregnant women in any trimester and followed until delivery to identify the outcomes of interest, preeclampsia (PE) and gestational hypertension (GH). The predictive capacity of fourth quartile measurements was compared with the first three quartiles of maternal subcutaneous and visceral adipose tissue from the periumbilical site (periumbilical m-SAT and m-VAT) (n = 155) and maternal adipose tissue from the epigastric site (preperitoneal m-SAT and m-VAT) (n = 261). The predictive ability of prepregnant body mass index (BMI) above 30 kg/m² for PE and GH was also assessed.

RESULTS

Fourth quartiles for the periumbilical ultrasound measurements were m-VAT 52.7 mm and m-SAT 21.7 mm. Preperitoneal site presents fourth quartiles m-VAT 15.2 mm and m-SAT 18.6 mm. Both m-VAT and m-SAT maternal periumbilical and preperitoneal sites are unable to predict PE, with the utmost sensitivity attributed to the periumbilical site m-SAT at 54%. The best PE predictor odds ratio (OR) found was the prepregnant BMI consistent with obesity, with an OR of 3.2 (95% CI 1.1-9.4), whereas the best OR to GH predictor was preperitoneal m-SAT with 8.9 (95% CI 2.3-34.6).

CONCLUSION

PE pathogenic mechanisms related to maternal abdominal adipose tissue include differences in molecular, cytological, and tissue levels not detected by ultrasound in a quantified gray scale assessment. Periumbilical or epigastric m-VAT use is not able to predict PE during pregnancy.

Aspirin use during pregnancy and the risk of bleeding complications: a Swedish population-based cohort study

BACKGROUND

Aspirin is offered to pregnant women to prevent preeclampsia, a severe obstetrical complication. Large studies of nonpregnant populations have consistently shown that aspirin prophylaxis increases the risk of hemorrhagic complications. However, there have not been any population-based studies investigating this in a pregnant population.

OBJECTIVE

This study aimed to investigate whether aspirin use during pregnancy is associated with an increased risk of bleeding complications.

STUDY DESIGN

We performed a register-based cohort study using the Swedish Pregnancy Register wherein we examined 313,624 women giving birth between January 2013 and July 2017. Logistic regression was used to assess the risk of antepartum, intrapartum, and postpartum hemorrhage. A propensity score and inverse probability treatment weighting was used to generate an odds ratio that corrects for differences in baseline characteristics.

RESULTS

Aspirin use was registered in 4088 (1.3%) women during pregnancy. Compared with women who did not take aspirin, aspirin use was not associated with bleeding complications during the antepartum period (adjusted odds ratio, 1.22; 95% confidence interval, 0.97-1.54). However, aspirin users had a higher incidence of intrapartum bleeding (2.9% aspirin users vs 1.5% nonusers; adjusted odds ratio, 1.63; 95% confidence interval, 1.30-2.05), postpartum hemorrhage (10.2% vs 7.8%; adjusted odds ratio, 1.23; 95% confidence interval, 1.08-1.39), and postpartum hematoma (0.4% vs 0.1%; adjusted odds ratio, 2.21; 95% confidence interval, 1.13-4.34). The risk of a neonatal intracranial hemorrhage was also increased (0.07% vs 0.01%; adjusted odds ratio, 9.66; 95% confidence interval, 1.88-49.48). After stratifying by mode of birth, a higher incidence of bleeding among aspirin users was present for those who had a vaginal birth but not those who had a cesarean delivery.

CONCLUSION

Using aspirin during pregnancy is associated with increased postpartum bleeding and postpartum hematoma. It may also be associated with neonatal intracranial hemorrhage. When offering aspirin during pregnancy, these risks need to be weighed against the potential benefits.

Early Pregnancy Blood Pressure Elevations and Risk for Maternal and Neonatal Morbidity

OBJECTIVE

To investigate whether women with early pregnancy elevated blood pressure (BP) or stage 1 hypertension exhibit increased risk of preeclampsia and maternal or neonatal morbidity.

METHODS

We conducted a clinical cohort study of 18,162 women who delivered a singleton neonate from 2015 to 2018 and attended at least two prenatal appointments before 20 weeks of gestation. Data were collected within the Magee Obstetric Maternal and Infant database, an aggregate of prenatal and delivery health records. Early pregnancy BP was defined as average BP before 20 weeks of gestation, and women were classified with normal, elevated BP, stage 1 or 2 hypertension according to current guidelines. The primary outcome was preeclampsia. Secondary outcomes were severe maternal morbidity, placental abruption, gestational diabetes, and composite neonatal morbidity.

RESULTS

Overall, 75.2% of the women were categorized with normal BP, 13.9% with elevated BP, 5.4% with stage 1 hypertension, and 5.5% with stage 2 hypertension. Risk of preeclampsia increased in a stepwise fashion with increasing BP category, adjusted for covariates (normal BP, 4.7%, referent; elevated BP, 7.3%, adjusted odds ratio [aOR] 1.29, 95% CI 1.07-1.56; stage 1, 12.3%, aOR 2.35, 95% CI 1.86-2.96), and stage 2, 30.2%, aOR 6.49, 95% CI 5.34-7.89). Results were similar among black and white women. Gestational diabetes was more prevalent among women with stage 1 (11.4%; aOR 1.50, 95% CI 1.18-1.91] and stage 2 hypertension (14.2%; aOR 1.65, 95% CI 1.30-2.10). Severe maternal morbidity and neonatal morbidity were increased only among women with stage 2 hypertension (aOR 2.99, 95% CI 2.26-3.99, and aOR 2.67, 95% CI 2.28-3.12, respectively).

CONCLUSION

Women with elevated BP, and stage 1 and 2 hypertension in early pregnancy are at increased risk for preeclampsia. These findings emphasize the importance of applying the 2017 BP guidelines to reproductive-aged women. Strategies to incorporate these guidelines into obstetric care may also be warranted.

Pregestational diabetes in pregnancy: Complications, management, surveillance, and mechanisms of disease-A review

Diabetes is an increasingly common diagnosis among pregnant women. Pregestational diabetes is associated with an increase in many adverse pregnancy outcomes, which impact both on the woman and her fetus. The models of pregnancy care for women with diabetes are based largely on observational data or consensus opinion. Strategies for aneuploidy screening and monitoring for fetal well-being should be modified in women with diabetes. There is an increasing understanding of the mechanisms by which congenital anomalies and disorders of fetal growth occur, involving epigenetic modifications, changes in gene expression in critical developmental pathways, and oxidative stress. This knowledge may lead to pathways for improved care for these high-risk pregnancies.

Early and late onset pre-eclampsia and small for gestational age risk in subsequent pregnancies

BACKGROUND

Pre-eclampsia shares pathophysiology with intrauterine growth restriction.

OBJECTIVE

To investigate whether delivery of a small for gestational age (SGA) infant in the 1st pregnancy increases the risk of early and late onset pre-eclampsia in the 2nd pregnancy. Conversely, we investigated whether pre-eclampsia in the 1st pregnancy impacts SGA risk in the 2nd pregnancy.

STUDY DESIGN

We studied a cohort from the Dutch Perinatal Registry of 265,031 women with 1st and 2nd singleton pregnancies who delivered between 2000 and 2007. We analyzed 2nd pregnancy risks of early and late onset pre-eclampsia-defined by delivery before or after 34 gestational weeks-as well as SGA below the 5th and between the 5th and 10th percentiles risks with multivariable logistic regressions. Interaction terms between 1st pregnancy hypertension, pre-eclampsia, SGA, and delivery before or after 34 gestational weeks were included in the regressions.

RESULTS

First pregnancy early onset pre-eclampsia increased risk of SGA <5th percentile (OR 2.1, 95% CI 1.7-2.7) in the 2nd pregnancy. Late onset pre-eclampsia increased the SGA <5th percentile marginally (OR 1.1, 95% CI 1.0-1.3). In the absence of 1st pregnancy hypertensive disorder, women who delivered an SGA infant in their 1st pregnancy were at increased risk of 2nd pregnancy late onset pre-eclampsia (SGA <5th: OR 2.05, 95% CI 1.58-2.66; SGA 5-10th: OR 1.39, 95% CI 1.01-1.93). Early onset 2nd pregnancy pre-eclampsia risk was also increased, but this was only statistically significant for women who delivered an SGA infant below the 5th percentile in the 1st pregnancy (SGA <5th: OR 2.44, 95% CI 1.19-5.00; SGA 5-10th: OR 1.69, 95% CI 0.68-4.24;).

CONCLUSION

Women with 1st pregnancy early onset pre-eclampsia have increased risk of SGA <5th percentile in the 2nd pregnancy. SGA in the 1st pregnancy increases pre-eclampsia risk in the 2nd pregnancy even in the absence of hypertensive disorders in the 1st pregnancy, although absolute risks remain low. These findings strengthen the evidence base associating intrauterine growth restriction with early onset pre-eclampsia.

Hippo-YAP1 signaling pathway and severe preeclampsia (sPE) in the Chinese population

BACKGROUND

The present study aims to explore the possible mechanisms of Hippo-YAP1 signaling pathway in the development of severe preeclampsia (sPE).

METHODS

A total of 14 pregnancies complicated with severe preeclampsia as well as 14 healthy pregnancies were involved in this research from Department of Obstetrics, the First Affiliated Hospital of Xi'An Jiaotong University, from 15th March 2016 to 15th March 2018. The mRNA levels of YAP1, TAZ, MST1 and MST2 were tested via the RT-qPCR in the placentas between the two groups. Also, the protein expression degrees of YAP1, TAZ, MST 1 and MST 2 were detected using the technology of Western blotting. At the same time, immune-histochemistry method was performed to localize the expression of YAP1, TAZ, MST 1 and MST 2 proteins in the placentas between the two groups. Yes-associated protein expression was also detected in BeWo and HTR-8/SVneo. Overexpressed plasmid and YAP1 si-RNA were transfered into HTR-8/SVneo trophoblast cells. Transwell invasion assay was used to examine the role of YAP1 in the invasion of HTR-8/SVneo trophoblast cells.

RESULTS

In comparison with the normal pregnancy placentas, the mRNA levels of YAP (0.659 ± 0.169 vs. 1.758 ± 0.587, P < 0.001) and TAZ (1.148 ± 0.313 vs. 2.894 ± 0.470, P < 0.001) were decreased in the placentas of severe preeclampsia group while the mRNA levels of MST 1 (1.433 ± 0.306 vs. 0.663 ± 0.162, P < 0.001) and MST 2 (1.497 ± 0.378 vs. 0.554 ± 0.130, P < 0.001) were increased. The Western blotting shown that the expression degrees of YAP1 and TAZ proteins were significantly decreased in the placentas of severe preeclampsia, while the expression level of MST 1 and MST 2 was obviously increased. Furthermore, the staining intensity of YAP1 and TAZ were weaker in the placentas of the severe PE group while the staining intensity of MST 1 and MST 2 was significantly stronger in the placentas of the severe PE group. The invasion ability of the HTR-8/SVneo cells in the YAP1-overexpressed group was significantly higher than the corresponding control group ((313.7 ± 5.86) vs.(194.0 ± 4.00), P < 0.05) while the si-YAP1 group was significantly lower than that of the corresponding control group ((81.33 ± 2.52) vs. (204.67 ± 11.02), P < 0.05).

CONCLUSIONS

Hippo-YAP1 signaling pathway may play an essential role in the pathogenesis of sPE by regulating the invasion and proliferation of trophoblast.