Measurement properties of comorbidity indices in maternal health research: a systematic review

Impact of the 2017 revised Japanese obstetric hemorrhage management guidelines on tranexamic acid use in patients undergoing cesarean delivery: an interrupted time series analysis

BACKGROUND

Tranexamic acid is one component of a complex management algorithm for postpartum hemorrhage. In Japan, the 2010 obstetric hemorrhage management guidelines was revised in 2017, adding the recommendation for the administration of tranexamic acid for postpartum hemorrhage. This research aims to delineate the temporal trends in tranexamic acid administration in patients undergoing cesarean deliveries and to examine the impact of the obstetric hemorrhage management guidelines implementation.

METHODS

An interrupted time series analysis was conducted on data from patients who underwent cesarean deliveries from April 2012 to August 2021, sourced from Japan's nationwide health insurance claims database. We examined the trends of tranexamic acid usage and blood transfusion use before and after the implementation of the revised guidelines in 2017.

RESULTS

The study cohort comprised 91 166 cesarean deliveries. Prior to the guideline implementation, the rate of tranexamic acid usage decreased. Post-guidelines implementation, there was a statistically significant increase in the rate of tranexamic acid use, with a quarterly percentage change of 0.48% (95% confidence interval: 0.36 to 0.60; P < 0.001). The guidelines implementation in 2017 was not significantly associated with a change in the rate of transfusions.

CONCLUSIONS

This interrupted time series analysis demonstrated a significant increase in the rate of tranexamic acid administration following the implementation of the revised guidelines, reversing the previously observed downward trend. Our findings could reflect the impact of the revised guideline on the use of tranexamic acid for postpartum hemorrhage, but this did not translate to fewer blood transfusions.

Using multi-level regression to determine associations and estimate causes and effects in clinical anesthesia due to patient, practitioner and hospital or health system practice variability

In this research methods tutorial of clinical anesthesia, we will explore techniques to estimate the influence of a myriad of factors on patient outcomes. Big data that contain information on patients, treated by individual anesthesiologists and surgical teams, at different hospitals, have an inherent multi-level data structure (Fig. 1). While researchers often attempt to determine the association between patient factors and outcomes, that does not provide clinicians with the whole story. Patient care is clustered together according to clinicians and hospitals where they receive treatment. Therefore, multi-level regression models are needed to validly estimate the influence of each factor at each level. In addition, we will explore how to estimate the influence that variability-for example, one anesthesiologist deciding to do one thing, while another takes a different approach-has on outcomes for patients, using the intra-class correlation coefficient for continuous outcomes and the median odds ratio for binary outcomes. From this tutorial, you should acquire a clearer understanding of how to perform and interpret multi-level regression modeling and estimate the influence of variable clinical practices on patient outcomes in order to answer common but complex clinical questions. Fig. 1 Infographics.

The global burden, risk and inequality of maternal obstructed labor and uterine rupture from 1990 to 2019

BACKGROUND

Obstructed labor (OL) and uterine rupture (UR) are common obstetric complications. This study explored the burden, risk factors, decomposition, and health inequalities associated with OL and UR to improve global maternal health.

METHODS

This was a cross-sectional analysis study including data on OL and UR from the Global Burden of Diseases, and Risk Factors Study (GBD) 2019. The main outcome measures included the number and age-standardized rate (ASR) of incidence, disability-adjusted life years (DALYs), prevalence, and deaths.

RESULTS

The global burden of OL and UR has declined, with a decrease in incidence (number in 2019: 9,410,500.87, 95%UI 11,730,030.94 to 7,564,568.91; ASR in 2019: 119.64 per 100,000, 95%UI 149.15 to 96.21; estimated annual percentage change [EAPC] from 1990 to 2019: -1.34, 95% CI -1.41 to -1.27) and prevalence over time. However, DALYs (number in 2019: 999,540.67, 95%UI 1,209,749.35 to 817,352.49; ASR in 2019: 12.92, 95%UI 15.63 to 10.56; EAPC from 1990 to 2019: -0.91, 95% CI -1.26 to -0.57) and deaths remain significant. ASR of DALYs increased for the 10-14 year-old age group (2.01, 95% CI 1.53 to 2.5), the 15-19 year-old age group (0.07, 95% CI -0.47 to 0.61), Andean Latin America (3.47, 95% CI 3.05 to 3.89), and Caribbean (4.16, 95% CI 6 to 4.76). Iron deficiency was identified as a risk factor for OL and UR, and its impact varied across different socio-demographic indices (SDIs). Decomposition analysis showed that population growth primarily contributed to the burden, especially in low SDI regions. Health inequalities were evident, the slope and intercept for DALYs were - 47.95 (95% CI -52.87 to -43.02) and - 29.29 (95% CI -32.95 to -25.63) in 1990, 39.37 (95%CI 36.29 to 42.45) and 24.87 (95%CI 22.56 to 27.18) in 2019. Concentration indices of ASR-DALYs were - 0.2908 in 1990 and - 0.2922 in 2019.

CONCLUSION

This study highlights the significant burden of OL and UR and emphasizes the need for continuous efforts to reduce maternal mortality and morbidity. Understanding risk factors and addressing health inequalities are crucial for the development of effective interventions and policies to improve maternal health outcomes globally.

The association between midwifery staffing and reported harmful incidents: a cross-sectional analysis of routinely collected data

BACKGROUND

Independent inquiries have identified that appropriate staffing in maternity units is key to enabling quality care and minimising harm, but optimal staffing levels can be difficult to achieve when there is a shortage of midwives. The services provided and how they are staffed (total staffing, skill-mix and deployment) have been changing, and the effects of workforce changes on care quality and outcomes have not been assessed. This study aims to explore the association between daily midwifery staffing levels and the rate of reported harmful incidents affecting mothers and babies.

METHODS

We conducted a cross-sectional analysis of daily reports of clinical incidents in maternity inpatient areas matched with inpatient staffing levels for three maternity services in England, using data from April 2015 to February 2020. Incidents resulting in harm to mothers or babies was the primary outcome measure. Staffing levels were calculated from daily staffing rosters, quantified in Hours Per Patient Day (HPPD) for midwives and maternity assistants. Understaffing was defined as staffing below the mean for the service. A negative binomial hierarchical model was used to assess the relationship between exposure to low staffing and reported incidents involving harm.

RESULTS

The sample covered 106,904 maternal admissions over 46 months. The rate of harmful incidents in each of the three services ranged from 2.1 to 3.0 per 100 admissions across the study period. Understaffing by registered midwives was associated with an 11% increase in harmful incidents (adjusted IRR 1.110, 95% CI 1.002,1.229). Understaffing by maternity assistants was not associated with an increase in harmful incidents (adjusted IRR 0.919, 95% 0.813,1.039). Analysis of specific types of incidents showed no statistically significant associations, but most of the point estimates were in the direction of increased incidents when services were understaffed.

CONCLUSION

When there is understaffing by registered midwives, more harmful incidents are reported but understaffing by maternity assistants is not associated with higher risk of harms. Adequate registered midwife staffing levels are crucial for maintaining safety. Changes in the profile of maternity service workforces need to be carefully scrutinised to prevent mothers and babies being put at risk of avoidable harm.

Patterns of multiple chronic conditions in pregnancy: Population-based study using latent class analysis

BACKGROUND

Adults with multiple chronic conditions (MCC) are a heterogeneous population with elevated risk of future adverse health outcomes. Yet, despite the increasing prevalence of MCC globally, data about MCC in pregnancy are scarce.

OBJECTIVES

To estimate the population prevalence of MCC in pregnancy and determine whether certain types of chronic conditions cluster together among pregnant women with MCC.

METHODS

We conducted a population-based cohort study in Ontario, Canada, of all 15-55-year-old women with a recognised pregnancy, from 2007 to 2020. MCC was assessed from a list of 22 conditions, identified using validated algorithms. We estimated the prevalence of MCC. Next, we used latent class analysis to identify classes of co-occurring chronic conditions in women with MCC, with model selection based on parsimony, clinical interpretability and statistical fit.

RESULTS

Among 2,014,508 pregnancies, 324,735 had MCC (161.2 per 1000, 95% confidence interval [CI] 160.6, 161.8). Latent class analysis resulted in a five-class solution. In four classes, mood and anxiety disorders were prominent and clustered with one additional condition, as follows: Class 1 (22.4% of women with MCC), osteoarthritis; Class 2 (23.7%), obesity; Class 3 (15.8%), substance use disorders; and Class 4 (22.1%), asthma. In Class 5 (16.1%), four physical conditions clustered together: obesity, asthma, chronic hypertension and diabetes mellitus.

CONCLUSIONS

MCC is common in pregnancy, with sub-types dominated by co-occurring mental and physical health conditions. These data show the importance of preconception and perinatal interventions, particularly integrated care strategies, to optimise treatment and stabilisation of chronic conditions in women with MCC.

Anesthesia practice for Cesarean delivery in Japan: a retrospective cohort study

PURPOSE

General anesthesia for Cesarean delivery affects maternal and neonatal outcomes. We aimed to evaluate temporal trends in anesthesia management for Cesarean deliveries over 16 years and analyze interinstitutional variations in general anesthesia use in Japan.

METHODS

In this retrospective cohort study, we obtained patient data from the nationwide health insurance claims database containing data for ten million individuals. We included patients who underwent Cesarean delivery between 1 January 2005 and 31 August 2021. The primary outcome was the use of general anesthesia. We evaluated institutional variations in general anesthesia use in medical facilities using two-level hierarchical logistic regression analyses with median odds ratios and intraclass correlation coefficients.

RESULTS

The cohort included 86,793 patients who underwent 102,617 Cesarean deliveries at 2,496 institutions. General anesthesia was used in 3.7% (95% confidence interval [CI], 3.6 to 3.9) of all Cesarean deliveries. The temporal trend in the use of general anesthesia decreased gradually from 10.8% in 2005 to 2.9% in 2021 (P for trend < 0.001). The adjusted median odds ratio for medical facilities was 6.1 (95% CI, 5.9 to 6.7), and the intraclass correlation coefficient was 0.52 (95% CI, 0.51 to 0.55).

CONCLUSION

Although the rate of general anesthesia use for Cesarean delivery in Japan decreased gradually from 2005 to 2021, general anesthesia was used in 3.7% of all Cesarean deliveries. The use of general anesthesia varied significantly across institutions, and 52% of the overall variations in general anesthesia practice can be explained by differences between facilities.

The development of a core outcome set for studies of pregnant women with multimorbidity

BACKGROUND

Heterogeneity in reported outcomes can limit the synthesis of research evidence. A core outcome set informs what outcomes are important and should be measured as a minimum in all future studies. We report the development of a core outcome set applicable to observational and interventional studies of pregnant women with multimorbidity.

METHODS

We developed the core outcome set in four stages: (i) a systematic literature search, (ii) three focus groups with UK stakeholders, (iii) two rounds of Delphi surveys with international stakeholders and (iv) two international virtual consensus meetings. Stakeholders included women with multimorbidity and experience of pregnancy in the last 5 years, or are planning a pregnancy, their partners, health or social care professionals and researchers. Study adverts were shared through stakeholder charities and organisations.

RESULTS

Twenty-six studies were included in the systematic literature search (2017 to 2021) reporting 185 outcomes. Thematic analysis of the focus groups added a further 28 outcomes. Two hundred and nine stakeholders completed the first Delphi survey. One hundred and sixteen stakeholders completed the second Delphi survey where 45 outcomes reached Consensus In (≥70% of all participants rating an outcome as Critically Important). Thirteen stakeholders reviewed 15 Borderline outcomes in the first consensus meeting and included seven additional outcomes. Seventeen stakeholders reviewed these 52 outcomes in a second consensus meeting, the threshold was ≥80% of all participants voting for inclusion. The final core outcome set included 11 outcomes. The five maternal outcomes were as follows: maternal death, severe maternal morbidity, change in existing long-term conditions (physical and mental), quality and experience of care and development of new mental health conditions. The six child outcomes were as follows: survival of baby, gestational age at birth, neurodevelopmental conditions/impairment, quality of life, birth weight and separation of baby from mother for health care needs.

CONCLUSIONS

Multimorbidity in pregnancy is a new and complex clinical research area. Following a rigorous process, this complexity was meaningfully reduced to a core outcome set that balances the views of a diverse stakeholder group.

Key outcomes for reporting in studies of pregnant women with multiple long-term conditions: a qualitative study

BACKGROUND

Maternal multiple long-term conditions are associated with adverse outcomes for mother and child. We conducted a qualitative study to inform a core outcome set for studies of pregnant women with multiple long-term conditions.

METHODS

Women with two or more pre-existing long-term physical or mental health conditions, who had been pregnant in the last five years or planning a pregnancy, their partners and health care professionals were eligible. Recruitment was through social media, patients and health care professionals' organisations and personal contacts. Participants who contacted the study team were purposively sampled for maximum variation. Three virtual focus groups were conducted from December 2021 to March 2022 in the United Kingdom: (i) health care professionals (n = 8), (ii) women with multiple long-term conditions (n = 6), and (iii) women with multiple long-term conditions (n = 6) and partners (n = 2). There was representation from women with 20 different physical health conditions and four mental health conditions; health care professionals from obstetrics, obstetric/maternal medicine, midwifery, neonatology, perinatal psychiatry, and general practice. Participants were asked what outcomes should be reported in all studies of pregnant women with multiple long-term conditions. Inductive thematic analysis was conducted. Outcomes identified in the focus groups were mapped to those identified in a systematic literature search in the core outcome set development.

RESULTS

The focus groups identified 63 outcomes, including maternal (n = 43), children's (n = 16) and health care utilisation (n = 4) outcomes. Twenty-eight outcomes were new when mapped to the systematic literature search. Outcomes considered important were generally similar across stakeholder groups. Women emphasised outcomes related to care processes, such as information sharing when transitioning between health care teams and stages of pregnancy (continuity of care). Both women and partners wanted to be involved in care decisions and to feel informed of the risks to the pregnancy and baby. Health care professionals additionally prioritised non-clinical outcomes, including quality of life and financial implications for the women; and longer-term outcomes, such as children's developmental outcomes.

CONCLUSIONS

The findings will inform the design of a core outcome set. Participants' experiences provided useful insights of how maternity care for pregnant women with multiple long-term conditions can be improved.

Maternal and child outcomes for pregnant women with pre-existing multiple long-term conditions: protocol for an observational study in the UK

INTRODUCTION

One in five pregnant women has multiple pre-existing long-term conditions in the UK. Studies have shown that maternal multiple long-term conditions are associated with adverse outcomes. This observational study aims to compare maternal and child outcomes for pregnant women with multiple long-term conditions to those without multiple long-term conditions (0 or 1 long-term conditions).

METHODS AND ANALYSIS

Pregnant women aged 15-49 years old with a conception date between 2000 and 2019 in the UK will be included with follow-up till 2019. The data source will be routine health records from all four UK nations (Clinical Practice Research Datalink (England), Secure Anonymised Information Linkage (Wales), Scotland routine health records and Northern Ireland Maternity System) and the Born in Bradford birth cohort. The exposure of two or more pre-existing, long-term physical or mental health conditions will be defined from a list of health conditions predetermined by women and clinicians. The association of maternal multiple long-term conditions with (a) antenatal, (b) peripartum, (c) postnatal and long-term and (d) mental health outcomes, for both women and their children will be examined. Outcomes of interest will be guided by a core outcome set. Comparisons will be made between pregnant women with and without multiple long-term conditions using modified Poisson and Cox regression. Generalised estimating equation will account for the clustering effect of women who had more than one pregnancy episode. Where appropriate, multiple imputation with chained equation will be used for missing data. Federated analysis will be conducted for each dataset and results will be pooled using random-effects meta-analyses.

ETHICS AND DISSEMINATION

Approval has been obtained from the respective data sources in each UK nation. Study findings will be submitted for publications in peer-reviewed journals and presented at key conferences.

Trend in neuraxial morphine use and postoperative analgesia after cesarean delivery in Japan from 2005 to 2020

The increasing rate of cesarean deliveries warrants obstetric anesthesiologists to deliver high-quality post-cesarean delivery analgesia. The aim of this study was to evaluate the temporal trends in the use of neuraxial morphine for cesarean deliveries and to describe the current postoperative analgesia practices. A retrospective cohort study using nationwide health insurance claims databases was conducted from 2005 to 2020 in Japan. Pregnant women who had undergone cesarean deliveries were included. The annual rate of neuraxial morphine use was extracted and analyzed. Additionally, we explored the patient- and facility-level factors associated with neuraxial morphine use through a multilevel logistic regression analysis. The cohort included 65,208 cesarean delivery cases from 2275 institutions. The prevalence of neuraxial morphine use was 16.0% (95% confidence interval [CI], 15.8-16.3) in the overall cohort. Intrathecal morphine was used in 20.6% (95% CI, 20.2-21.0) of spinal anesthesia cases. The trend in neuraxial morphine use steadily increased from 2005 to 2020. The significant predictors of neuraxial morphine use included spinal anesthesia, recent surgery, large medical facilities, and academic hospitals. Variations in the utilization of postoperative analgesia were observed. Our study described the current trend of neuraxial morphine use and the variation in postoperative analgesia practice in Japan.

Current Epidemiology of the General Anesthesia Practice for Cesarean Delivery Using a Nationwide Claims Database in Japan: A Descriptive Study

The current status of general anesthesia practice for cesarean delivery in Japan remains unknown. Therefore, using a nationwide claims database, we aimed to investigate general anesthesia use for cesarean delivery over a period of 15 years, and to analyze the general anesthesia practice in Japan. Patients who claimed the Japanese general anesthesia claim code (L008) for cesarean delivery between 1 January 2005, and 31 March 2020, were analyzed. Primary endpoint was the prevalence of general anesthesia use. We used two definitions of general anesthesia: L008 code only (insurance definition) and combination of the L008 code with muscle relaxant use (clinical definition). The general anesthesia claim cohort (L008) included 10,972 cesarean deliveries at 1111 institutions from 2005 to 2020. Muscle relaxants were used in 27.3% of L008 claims cases. The rate of general anesthesia use for cesarean delivery ranged from 3.9% in clinical definition to 14.4% in insurance definition of all cesarean deliveries. We observed a temporal trend of gradual decrease in general anesthesia use, regardless of its definition (p for trend < 0.001). We recommend the clinical definition of general anesthesia as the combination of L008 code and muscle relaxant use in a claims-based approach.

Doula care across the maternity care continuum and impact on maternal health: Evaluation of doula programs across three states using propensity score matching

Background

This evaluation of doula care emerges at a time when maternal mortality in the U.S. outranks every country in the developed world. Study objectives were to: 1) examine when over the maternity care continuum and with whom (i.e., clinical providers) doula care provides the greatest benefits to clinical health outcomes and health care utilization; and 2) evaluate whether women gain differential benefits from doulas depending upon race/ethnicity and health status.

Methods

We conducted a retrospective cohort study using Medicaid medical claims from California, Florida, and a northeastern state (USA) to compare maternal health outcomes between women who did and did not receive doula care between January 1, 2014 and December 31, 2020. We used propensity score matching and logistic regression models to calculate associations between selected health outcomes and doula care. Our analysis included 298 pairs of women matched on age, race/ethnicity, state, socioeconomic status, and hospital type (teaching or non-teaching).

Findings

Women who received doula care had 52.9% lower odds of cesarean delivery (OR: 0.471 95% CI: 0.29-0.79) and 57.5% lower odds of postpartum depression/postpartum anxiety (PPD/PPA) (OR: 0.425 95% CI: 0.22-0.82). Doulas who provided care with a clinical team that included a midwife most consistently showed a reduction in odds of cesarean delivery, regardless of the trimester when doula care was received. Women who received doula care during labor and birth, but not necessarily during pregnancy, showed a 64.7% reduction in odds of PPA/PPD (OR: 0.353 95% CI: 0.16-0.78) of PPA/PPD.

Interpretation

The use of doulas appears an effective strategy for improving maternal health, especially among socioeconomically vulnerable and marginalized minority populations. Future studies could address research gaps through focusing on the relationship between doula care received in the postpartum period and postpartum health.

Funding

No sources of funding were used to assist in the preparation of this manuscript. Research was completed as part of the usual employment obligations to Anthem, Inc.

Epidemiology of pre-existing multimorbidity in pregnant women in the UK in 2018: a population-based cross-sectional study

BACKGROUND

Although maternal death is rare in the United Kingdom, 90% of these women had multiple health/social problems. This study aims to estimate the prevalence of pre-existing multimorbidity (two or more long-term physical or mental health conditions) in pregnant women in the United Kingdom (England, Northern Ireland, Wales and Scotland).

STUDY DESIGN

Pregnant women aged 15-49 years with a conception date 1/1/2018 to 31/12/2018 were included in this population-based cross-sectional study, using routine healthcare datasets from primary care: Clinical Practice Research Datalink (CPRD, United Kingdom, n = 37,641) and Secure Anonymized Information Linkage databank (SAIL, Wales, n = 27,782), and secondary care: Scottish Morbidity Records with linked community prescribing data (SMR, Tayside and Fife, n = 6099). Pre-existing multimorbidity preconception was defined from 79 long-term health conditions prioritised through a workshop with patient representatives and clinicians.

RESULTS

The prevalence of multimorbidity was 44.2% (95% CI 43.7-44.7%), 46.2% (45.6-46.8%) and 19.8% (18.8-20.8%) in CPRD, SAIL and SMR respectively. When limited to health conditions that were active in the year before pregnancy, the prevalence of multimorbidity was still high (24.2% [23.8-24.6%], 23.5% [23.0-24.0%] and 17.0% [16.0 to 17.9%] in the respective datasets). Mental health conditions were highly prevalent and involved 70% of multimorbidity CPRD: multimorbidity with ≥one mental health condition/s 31.3% [30.8-31.8%]). After adjusting for age, ethnicity, gravidity, index of multiple deprivation, body mass index and smoking, logistic regression showed that pregnant women with multimorbidity were more likely to be older (CPRD England, adjusted OR 1.81 [95% CI 1.04-3.17] 45-49 years vs 15-19 years), multigravid (1.68 [1.50-1.89] gravidity ≥ five vs one), have raised body mass index (1.59 [1.44-1.76], body mass index 30+ vs body mass index 18.5-24.9) and smoked preconception (1.61 [1.46-1.77) vs non-smoker).

CONCLUSION

Multimorbidity is prevalent in pregnant women in the United Kingdom, they are more likely to be older, multigravid, have raised body mass index and smoked preconception. Secondary care and community prescribing dataset may only capture the severe spectrum of health conditions. Research is needed urgently to quantify the consequences of maternal multimorbidity for both mothers and children.

Neighbourhood material deprivation and severe maternal morbidity: a population-based cohort study in Ontario, Canada

OBJECTIVES

Rates of age-associated severe maternal morbidity (SMM) have increased in Canada, and an association with neighbourhood income is well established. Our aim was to examine SMM trends according to neighbourhood material deprivation quintile, and to assess whether neighbourhood deprivation effects are moderated by maternal age.

DESIGN, SETTING AND PARTICIPANTS

A population-based retrospective cohort study using linked administrative databases in Ontario, Canada. We included primiparous women with a live birth or stillbirth at ≥20 weeks' gestational age.

PRIMARY OUTCOME

SMM from pregnancy onset to 42 days postpartum. We calculated SMM rate differences (RD) and rate ratios (RR) by neighbourhood material deprivation quintile for each of four 4-year cohorts from 1 April 2002 to 31 March 2018. Log-binomial multivariable regression adjusted for maternal age, demographic and pregnancy-related variables.

RESULTS

There were 1 048 845 primiparous births during the study period. The overall rate of SMM was 18.0 per 1000 births. SMM rates were elevated for women living in areas with high material deprivation. In the final 4-year cohort, the RD between women living in high vs low deprivation neighbourhoods was 3.91 SMM cases per 1000 births (95% CI: 2.12 to 5.70). This was higher than the difference observed during the first 4-year cohort (RD 2.09, 95% CI: 0.62 to 3.56). SMM remained associated with neighbourhood material deprivation following multivariable adjustment in the pooled sample (RR 1.16, 95% CI: 1.11 to 1.21). There was no evidence of interaction with maternal age.

CONCLUSION

SMM rate increases were more pronounced for primiparous women living in neighbourhoods with high material deprivation compared with those living in low deprivation areas. This raises concerns of a widening social gap in maternal health disparities and highlights an opportunity to focus risk reduction efforts toward disadvantaged women during pregnancy and postpartum.

Society for Maternal-Fetal Medicine Consult Series #54: Assessing the risk of maternal morbidity and mortality

The rates of maternal morbidity and mortality in the United States demand a comprehensive approach to assessing pregnancy-related risks. Numerous medical and nonmedical factors contribute to maternal morbidity and mortality. Reducing the number of women who experience pregnancy morbidity requires identifying which women are at greatest risk and initiating appropriate interventions early in the reproductive life course. The purpose of this Consult is to educate all healthcare practitioners about factors contributing to a high-risk pregnancy, strategies to assess maternal health risks due to pregnancy, and the importance of risk assessment across the reproductive spectrum in reducing maternal morbidity and mortality.

Association of Maternal Comorbidity With Severe Maternal Morbidity: A Cohort Study of California Mothers Delivering Between 1997 and 2014

BACKGROUND

Rates of maternal mortality and severe maternal morbidity (SMM) are higher in the United States than in other high-resource countries and are increasing further.

OBJECTIVE

To examine the association of maternal comorbid conditions, age, body mass index, and previous cesarean birth with occurrence of SMM.

DESIGN

Population-based cohort study using linked delivery hospitalization discharge data and vital records.

SETTING

California, 1997 to 2014.

PATIENTS

All 9 179 472 mothers delivering in California during 1997 to 2014.

MEASUREMENTS

SMM rate, total and without transfusion-only cases; 2019 maternal comorbidity index.

RESULTS

Total SMM increased by 160% during this time, and SMM excluding transfusion-only cases increased by 53%. Medical comorbid conditions were associated with an increasing portion of SMM occurrences. Medical comorbid conditions increased over the study period by 111%, and obstetric comorbid conditions increased by 30% to 40%. Identified medical comorbid conditions had high relative risks ranging from 1.3 to 14.3 for total SMM and even higher relative risks for nontransfusion SMM (to 32.4). The obstetric comorbidity index that is most often used may be undervaluing the degree of association with SMM.

LIMITATIONS

Hospital discharge diagnosis files and birth certificate records can have misclassifications and may not include all relevant clinical data or social determinants. The period for analysis ended in 2014 to avoid the transition to the International Classification of Diseases, 10th Revision, Clinical Modification, and therefore missed more recent years.

CONCLUSION

Obstetric and, particularly, medical comorbid conditions are increasing among women who develop SMM. The maternal comorbidity index is a promising tool for patient risk assessment and case-mix adjustment, but refinement of factor weights may be indicated.

PRIMARY FUNDING SOURCE

National Institutes of Health.

Comparison of four prognostic scales for predicting mortality in patients with severe maternal morbidity

OBJECTIVE

To compare the prognostic validity of the APACHE II-M and O-SOFA scales versus the APACHE II and SOFA to predict mortality in patients with severe maternal morbidity.

DESIGN

A retrospective, longitudinal and analytical cohort study was carried out.

SETTING

Medical-surgical intensive care unit (ICU) of a tertiary hospital.

PATIENTS

Pregnant or puerperal patients of any age admitted to the ICU.

INTERVENTIONS

Calculation of prognostic scores upon admission.

VARIABLES OF INTEREST

APACHE II, SOFA, APACHE II-M and O-SOFA scores and maternal mortality.

RESULTS

A total of 141 patients were included. The majority (70.2%) were puerperal. The most frequent diagnosis was gestational hypertensive disease (50 cases). The discrimination of each prognostic model was estimated with the area under the ROC curve (AUC-ROC). The calibration was estimated using the mortality ratio and the Hosmer-Lemeshow statistic. The four scales discriminated between survivors and non-survivors with areas under the curve >0.85. The APACHE II-M model was the predictive model with the highest discrimination and calibration. In the Hosmer-Lemeshow regression analysis, mortality as predicted by the APACHE II and O-SOFA was significantly different from the observed mortality.

CONCLUSIONS

The APACHE II-M exhibited the greatest prognostic validity in predicting maternal mortality. This difference was given by its improvement in calibration.

Variability in intensive care unit admission among pregnant and postpartum women in Canada: a nationwide population-based observational study

Background

Pregnancy-related critical illness results in approximately 300,000 deaths globally each year. The objective was to describe the variation in ICU admission and the contribution of patient- and hospital-based factors in ICU admission among acute care hospitals for pregnant and postpartum women in Canada.

Methods

A nationwide cohort study between 2004 and 2015, comprising all pregnant or postpartum women admitted to Canadian hospitals. The primary outcome was ICU admission. Secondary outcomes were severe maternal morbidity (a potentially life-threatening condition) and maternal death (during and within 6 weeks after pregnancy). The proportion of total variability in ICU admission rates due to the differences among hospitals was described using the median odds ratio from multi-level logistic regression models, adjusting for individual hospital clusters.

Results

There were 3,157,248 identifiable pregnancies among women admitted to 342 Canadian hospitals. The overall ICU admission rate was 3.2 per 1000 pregnancies. The rate of severe maternal morbidity was 15.8 per 1000 pregnancies, of which 10% of women were admitted to an ICU. The most common severe maternal morbidity events included postpartum hemorrhage (n = 16,364, 0.52%) and sepsis (n = 11,557, 0.37%). Of the 195 maternal deaths (6.2 per 100,000 pregnancies), only 130 (67%) were admitted to ICUs. Patients dying in hospital, without admission to ICU, included those with cardiovascular compromise, hemorrhage, and sepsis. For 2 pregnant women with similar characteristics at different hospitals, the average (median) odds of being admitted to ICU was 1.92 in 1 hospital compared to another. Hospitals admitting the fewest number of pregnant patients had the highest incidence of severe maternal morbidity and mortality. Patient-level factors associated with ICU admission were maternal comorbidity index (OR 1.88 per 1 unit increase, 95%CI 1.86–1.99), urban residence (OR 1.09, 95%CI 1.02–1.16), and residing at the lowest income quintile (OR 1.44, 95%CI 1.34–1.55).

Conclusions

Most women who experience severe maternal morbidity are not admitted to an ICU. There exists a wide hospital-level variability in ICU admission, with patients living in urban locations and patients of lowest income levels most likely to be admitted to ICU. Cardiovascular compromise, hemorrhage, and sepsis represent an opportunity for improved patient care and outcomes.

Long-term mortality in mothers of infants with neonatal abstinence syndrome: A population-based parallel-cohort study in England and Ontario, Canada

BACKGROUND

Opioid addiction is a major public health threat to healthy life expectancy; however, little is known of long-term mortality for mothers with opioid use in pregnancy. Pregnancy and delivery care are opportunities to improve access to addiction and supportive services. Treating neonatal abstinence syndrome (NAS) as a marker of opioid use during pregnancy, this study reports long-term maternal mortality among mothers with a birth affected by NAS in relation to that of mothers without a NAS-affected birth in 2 high-prevalence jurisdictions, England and Ontario, Canada.

METHODS AND FINDINGS

We conducted a population-based study using linked administrative health data to develop parallel cohorts of mother-infant dyads in England and Ontario between 2002 and 2012. The study population comprised 13,577 and 4,966 mothers of infants with NAS and 4,205,675 and 929,985 control mothers in England and Ontario, respectively. Death records captured all-cause maternal mortality after delivery through March 31, 2016, and cause-specific maternal mortality to December 31, 2014. The primary exposure was a live birth of an infant with NAS, and the main outcome was all deaths among mothers following their date of delivery. We modelled the association between NAS and all-cause maternal mortality using Cox regression, and the cumulative incidence of cause-specific mortality within a competing risks framework. All-cause mortality rates, 10-year cumulative incidence risk of death, and crude and age-adjusted hazard ratios were calculated. Estimated crude 10-year mortality based on Kaplan-Meier curves in mothers of infants with NAS was 5.1% (95% CI 4.7%-5.6%) in England and 4.6% (95% CI 3.8%-5.5%) in Ontario versus 0.4% (95% CI 0.41%-0.42%) in England and 0.4% (95% CI 0.38%-0.41%) in Ontario for controls (p < 0.001 for all comparisons). Survival curves showed no clear inflection point or period of heightened risk. The crude hazard ratio for all-cause mortality was 12.1 (95% 11.1-13.2; p < 0.001) in England and 11.4 (9.7-13.4; p < 0.001) in Ontario; age adjustment did not reduce the hazard ratios. The cumulative incidence of death was higher among NAS mothers than controls for almost all causes of death. The majority of deaths were by avoidable causes, defined as those that are preventable, amenable to care, or both. Limitations included lack of direct measures of maternal opioid use, other substance misuse, and treatments or supports received.

CONCLUSIONS

In this study, we found that approximately 1 in 20 mothers of infants with NAS died within 10 years of delivery in both England and Canada-a mortality risk 11-12 times higher than for control mothers. Risk of death was not limited to the early postpartum period targeted by most public health programs. Policy responses to the current opioid epidemic require effective strategies for long-term support to improve the health and welfare of opioid-using mothers and their children.

[Extragenital diseases, comorbidities, and polymorbidity in maternal death]

OBJECTIVE

To study the structure and significance of comorbidities and polymorbidity in maternal death.

MATERIAL AND METHODS

Sixty-five autopsy protocols of maternal deaths in the Novosibirsk Region in the period of 1994 to 2018 were analyzed.

RESULTS

Extragenital diseases are the leading diseases in the nosological structure in maternal mortality. Preeclampsia/exlampsia and obstetric hemorrhages lost their leading positions. The increasing role of extragenital pathology in the structure of maternal mortality is due to many factors, such as a larger number of comorbidities and polymorbidity, in pregnant women. Infectious diseases, benign and malignant tumors, and diseases of the heart and blood vessels are the main diseases in the structure of extragenital diseases.

Risk prediction models for maternal mortality: A systematic review and meta-analysis

PURPOSE

Pregnancy-related critical illness leads to death for 3-14% of affected women. Although identifying patients at risk could facilitate preventive strategies, guide therapy, and help in clinical research, no prior systematic review of this literature exploring the validity of risk prediction models for maternal mortality exists. Therefore, we have systematically reviewed and meta-analyzed risk prediction models for maternal mortality.

METHODS

Search strategy: MEDLINE, EMBASE and Scopus, from inception to May 2017. Selection criteria: Trials or observational studies evaluating risk prediction models for maternal mortality. Data collection and analysis: Two reviewers independently assessed studies for eligibility and methodological quality, and extracted data on prediction performance.

RESULTS

Thirty-eight studies that evaluated 12 different mortality prediction models were included. Mortality varied across the studies, with an average rate 10.4%, ranging from 0 to 41.7%. The Collaborative Integrated Pregnancy High-dependency Estimate of Risk (CIPHER) model and the Maternal Severity Index had the best performance, were developed and validated from studies of obstetric population with a low risk of bias. The CIPHER applies to critically ill obstetric patients (discrimination: area under the receiver operating characteristic curve (AUC) 0.823 (0.811-0.835), calibration: graphic plot [intercept-0.09, slope 0.92]). The Maternal Severity Index applies to hospitalized obstetric patients (discrimination: AUC 0.826 [0.802-0.851], calibration: standardized mortality ratio 1.02 [0.86-1.20]).

CONCLUSIONS

Despite the high heterogeneity of the study populations and the limited number of studies validating the finally eligible prediction models, the CIPHER and the Maternal Severity Index are recommended for use among critically ill and hospitalized pregnant and postpartum women for risk adjustment in clinical research and quality improvement studies. Neither index has sufficient discrimination to be applicable for clinical decision making at the individual patient level.