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Abstract
Introduction and objective Maternal morbidity and mortality (MMM) is a public health concern in the USA, with Native American women experiencing higher rates than non-Hispanic White women. Research on risk factors for MMM among Native American women is limited. This systematic review comprehensively synthesizes and critically appraises the literature on risk factors for MMM experienced by Native American women.
Methods and analysis A systematic search was conducted on 10 October 2022 in PubMed, Embase, CINAHL and Scopus for articles published since 2012. Selection criteria included observational studies set in the USA, involving Native American women in the perinatal period, and examining the relationship between risk factors and MMM outcomes. Three reviewers screened and extracted data from the included studies, with risk of bias assessed using the National Institutes of Health Quality Assessment Tools. Data were analysed descriptively.
Results 15 studies were included. All studies used administrative databases, with settings, including nationwide (seven studies), statewide (four studies) and Indian reservations (four studies). The majority of studies focused on hypertensive disorders of pregnancy (eight studies) and severe maternal morbidity (SMM) (four studies). 26 risk factors were identified. Key risk factors included Native American race (six studies), rural maternal residency (four studies), overweight/obese body mass index (two studies), maternal age (two studies), nulliparity (two studies) and pre-existing medical conditions (one study).
Conclusion This review identified risk factors associated with MMM among Native American women, including rural residency, overweight or obesity and advanced maternal age. However, the findings also reveal a scarcity of research specific to this population, limiting the ability to fully understand these risk factors and develop effective interventions. These results emphasise the need for further research and culturally relevant studies to inform public health and address disparities for Native American women, particularly those in rural areas.
PROSPERO registration number CRD42022363405.
- Mortality
- OBSTETRICS
- PUBLIC HEALTH
- Systematic Review
- Pregnant Women
- Risk Factors
Data availability statement
All data relevant to the study are included in the article or uploaded as supplementary information. The original contributions presented in the study are included in the article’s supplemental material; further inquiries can be directed to the corresponding author.
This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.
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STRENGTHS AND LIMITATIONS OF THIS STUDY
The review searched a variety of scientific databases to identify a wide range of studies on maternal morbidity and mortality (MMM) in Native American women in the USA.
The review incorporated studies conducted on Indian reservations and within specific tribal health systems, providing insights tailored to the unique contexts and experiences of Native American women.
The review synthesizes and critically appraises the limited existing literature on risk factors for MMM specifically among Native American women in the USA.
Many included studies had small sample sizes or low percentages of Native American women, limiting the generalisability of the findings to this specific population.
Included studies relied on administrative databases (ie, hospital discharge database, vital records registries or electronic health records), which introduce potential reporting biases and misclassification issues, especially concerning the racial categorisation of Native American participants.
Introduction
Maternal morbidity and mortality (MMM) are alarming public health problems in the USA. The Centres for Disease Control (CDC) and Prevention define maternal mortality as the death of a woman during pregnancy, at delivery, or soon after delivery.1 Severe maternal morbidity (SMM) refers to complications during labour and delivery with short- and long-term health consequences (eg, sepsis, blood transfusion, preeclampsia or hysterectomy).2 3 The USA has one of the highest maternal mortality ratios of any high-income country, reporting 26.4 maternal deaths per 100 000 live births.4 In contrast, Finland has the lowest maternal mortality ratio of 3.8 deaths per 100 000 live births, a value nearly seven times lower than the USA.4 The SMM rate surged 75% from 1998 to 1999 to 129 per 10 000 delivery hospitalisations in 2008 and 2009.2 Rising rates of blood transfusions, acute renal failure, shock and other adverse outcomes primarily drove this increase.2 The rising MMM rates involve complex interactions of factors among patients and families, providers or facilities, overall systems and within the community at various points in a woman’s reproductive life cycle.5
Significant racial and ethnic health inequities persist in maternal health.6–9 Native American women are three to four times more likely to die than non-Hispanic White women from pregnancy-related complications and are three to five times more likely to experience SMM than non-Hispanic White women.6 10 11 Historical trauma, racism, colonisation, genocide, forced migration, reproductive coercion and cultural erasure contribute to these adverse outcomes.12–14 Native American women experience unique prolonged systemic barriers that create inequitable social conditions compared with other groups.14–16 Some systemic barriers include limited access to providers and birthing facilities.14 17 18 In addition, a history of forced sterilisation and forced infant and child separations has led to a strong distrust of the healthcare systems and providers, including the Indian Health Service.19–21
Rationale
A scoping review on Native American women and the leading causes of maternal mortality in the USA identified risk factors, such as historical trauma, inequities in healthcare availability, access and utilisation, pre-existing health conditions and rurality.22 A separate review of social determinants on pregnancy-related mortality and morbidity identified that race was a significant factor.3 However, the review neither provided a list of risk factors specific to Native American women nor did it identify a study that evaluated maternal deaths among Native American women.3 There is a need to explore further and assess the quality of research specific to MMM risk factors experienced by Native American women. Identifying this information can help identify areas for prevention focused on Native American communities.
Objective
To assess and critically appraise individual- and community-level risk factors for pregnancy-related morbidity and mortality experienced by Native American women in the USA.
Methods
This systematic review follows a protocol previously published, which provides a comprehensive framework for examining pregnancy-related mortality and morbidity among Native American women.23 Adhering to this pre-established protocol ensures methodological rigour and transparency, facilitating reproducibility and reliability in the findings presented.
Patient and public involvement
Patients and the public were not involved in the design, conduct, reporting or dissemination of this research.
Eligibility criteria
This systematic review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.24 Inclusion criteria for studies were: (1) observational study design; (2) study set in the USA; (3) population was Native American women in the perinatal (ie, the time surrounding childbirth) or puerperium period (ie, the time after childbirth up to 6 weeks); (4) outcomes focused on the measures of pregnancy-related mortality and morbidity; (5) examined the relationship between a risk factor/exposure and stated outcomes and (6) had a publication date between 1 January 2012 and 10 October 2022. This timeframe aligns with a new standard for identifying SMM published on 12 November 2012.2 Studies focusing on a different population were included if they offered a stratified analysis by race and contained a racial category for Native Americans. Studies were excluded if: (1) studies focused only on birth, neonatal or infant outcomes; (2) studies that did not examine the relationship between a risk factor/exposure and stated outcomes; (3) studies with settings outside of the USA; (4) studies that did not include findings for Native American women; (5) studies that focus on the preconception or postpartum phases; (6) studies were published outside of the specified time.
Information sources and search strategy
The search was carried out on 10 October 2022. The review searched scientific databases (PubMed, Embase, CINAHL and Scopus). With technical assistance from a health sciences librarian, the team used search tools and strategies, including shortening keywords where appropriate, using thesaurus terms and using database-specific controlled vocabulary (eg, Medical Subject Headings (MeSH)). The search strategy combined terms and search strings with the appropriate boolean operators. The complete search strategy is available in online supplemental appendix 1. Covidence was used to manage every stage of the systematic review, including screenings, data extractions and risk of bias assessments.25
Supplemental material
Selection process
Two independent reviewers screened titles and abstracts based on the eligibility criteria. If any disagreement occurred, a third reviewer arbitrated. After the titles and abstracts were screened, two independent reviewers screened full-text articles. The reasons for exclusion were noted at the full-text article stage.
Data collection process
Two independent reviewers extracted study details, such as location, study design, eligibility criteria, methods, year of the article, year(s) of study, data source, objectives, sample size and population, independent (risk factors) and dependent (outcomes) variables, key findings, measures of effect/association with p-values and confidence intervals and limitations. For any missing information, the lead author contacted the corresponding authors three times via email or phone to request information. Any discrepancies within data extraction were reviewed and discussed in a team setting.
Data items
Primary outcomes of interest were MMM, including SMM based on the CDCs list of 21 diagnoses and procedures (table 1).26
Outcomes of interest
This list was used to identify additional articles that did not use a composite outcome of SMM or mortality. Given the scope of this review, the terms ‘pregnancy complications’, ‘obstetric complications’, ‘labour complications’ and ‘near miss’ were added to the list of outcomes to increase the sensitivity of the review. Pregnancy, labour and obstetric complications encompass conditions occurring during or after pregnancy, ranging from minor discomforts to severe diseases requiring medical intervention, including both pregnancy-related conditions and pre-existing diseases in pregnant women.27 A near miss refers to a life-threatening event that does not result in death.28 The search strategy was pilot-tested in PubMed, finalised and adapted to other databases (box 1). The complete search strategy is available in online supplemental appendix 1. The results from each database-specific search strategy were downloaded from the respective databases and uploaded to the EndNote software.29 After removing the duplicates, the citations were imported into Covidence.
PubMed search strategy
birth[tiab] OR labor[tiab] OR delivery[tiab] OR mothers[tiab] OR maternal[tiab] OR “peripartum period”[mesh] OR peripartum[tiab] OR “labor, obstetric”[mesh] OR “obstetric*”[mesh] OR “obstetric*”[tiab] OR “pregnancy”[mesh] OR “pregnan*”[tiab] OR “perinatal”[tiab] OR “prenatal”[tiab] OR “parturition”[mesh] OR “parturition”[tiab]
“tribal” OR “tribe” OR “first nations” OR “indigenous peoples”[mesh] OR indigenous OR “health services, indigenous”[mesh] OR “american indians or alaska natives”[mesh] OR “american indian*” OR “indians, north american”[mesh] OR “native American” OR “alaska native”
“severe maternal morbidity” OR “near miss” OR “adverse maternal outcomes” OR “maternal mortality” OR “Near Miss, Healthcare”[Mesh] OR “Pregnancy/Adverse Effects”[Mesh] OR “Pregnancy/Injuries”[Mesh] OR “Pregnancy/Mortality”[Mesh] OR “Pregnancy/complications”[Mesh] OR “Obstetric Labor Complications”[Mesh] OR “Delivery, Obstetric/adverse effects”[Mesh] OR “Delivery, Obstetric/complications”[Mesh] OR “Delivery, Obstetric/mortality”[Mesh] OR “Maternal Mortality”[Mesh] OR “mortality”[mesh] OR “morbidity”[mesh] OR “pregnancy complications” OR mortality OR morbidity OR “labor complications” OR “delivery complications”
Search (#1 AND #2 AND #3)
Study risk of bias assessment and certainty assessment
Risk of bias was assessed using the National Institute’s of Health (NIH) Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies and Case–Control Studies to examine critical concepts for each study’s validity.30 Two independent reviewers assessed articles using the tool’s criteria and rated them as ‘good’, ‘fair’ or ‘poor’ quality. This rating was based on the percentage of ‘Yes’ responses out of the total applicable questions in each tool. A study will be rated as ‘good’ if it receives a ‘Yes’ response for ≥80% of the applicable NIH critical appraisal questions, ‘fair’ for 50%–79% and ‘poor’ for ≤49%. A ‘good’ rating meant there was the least risk of bias, and the results were considered valid.30 A ‘fair’ rating indicated susceptibility to some bias but was insufficient to invalidate its results and would vary in their strengths and weaknesses.30 A ‘poor’ rating indicated a significant risk of bias and invalidated its results.30 When the ratings differed, a third reviewer arbitrated an article’s rating.
Effect measures
Measures of effect, such as risk and ORs with 95% CI, were extracted. Descriptive statistics, such as prevalence and incidence, were also included.
Potential overlap in cohorts
Given the research scarcity on the population of interest and topic mentioned in this article, we attempted to manage for potential overlap in populations across different cohorts in the included studies. Several strategies were used to manage any potential overlap and ensure the integrity and accuracy of the findings. (1) Data sources for cohorts were meticulously documented, including specific populations covered by each study. (2) Cohorts were often segmented by geographic regions and demographic characteristics relevant to Native American women. (3) Assessed study periods to identify and address any potential overlap in cohorts.
Synthesis methods
Online supplemental appendix 2 provides a summary of study findings, including risk factors, outcomes and study characteristics. A descriptive synthesis was used due to the diversity in study designs, risk factors and outcomes, which precluded quantitative analysis. Risk factors were organised by socioecological levels (individual, family, community, society or systems) and grouped by outcome.31 For each risk factor, the table reports the number of studies analysing it and whether the effect was statistically significant.
Supplemental material
Results
Study selection and study characteristics
A total of 8220 articles were identified, of which 357 duplicates were removed, resulting in 7863 articles for screening (figure 1). During the screening process, there were 6967 agreements for inclusion and 896 conflicts resolved by an arbitrator, for an overall percent agreement of 88.6%. The selection process yielded 145 articles, of which 15 were included in the review.10 11 32–41 The most common reasons for study exclusion were the wrong patient population (41 studies), the wrong setting (22 studies) and the wrong type of publication (21 studies). Most (80.0%) studies used secondary data sources (ie, hospital discharge records, vital records, as such) to examine associations between risk factors and outcomes. There was an equal number of studies across three study designs (five studies each). The sample size across all studies ranged from 196 to 51 685 525 with a mean sample size of 4 479 962, a median of 72 697, an SD of 12 732 821.6 and an IQR of 2 123 375.0. Seven studies focused primarily on Native American women (ie, the study sample comprised mainly of Native American women).34–36 38–40 42 The remaining eight studies included Native American women as a subgroup in their sample.10 11 32 33 37 41 43 44 Of these eight studies, the percentage of Native American women that were a part of the overall sample ranged from 0.4% to 10.1%, and six of these studies had a proportion of Native American women in their sample that was ≤1.4%. The total number of Native American participants across all studies ranged from 196 to 4 92 771 with a mean of 57 266.5, a median of 7107, an SD of 129 234.2 and an IQR of 26 817.0. Study settings included nationwide (7/15 studies),10 11 37 38 41 43 44 statewide (4/15 studies)32 33 39 40 and on Indian reservations (4/15 studies).34–36 42
Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagram.
Risk of bias in studies
14 studies were rated as ‘good’ and 1 was rated as ‘fair’ according to the NIHs Study Quality Assessment Tools. See online supplemental appendix 4 for individual assessments of quality. All cohort and cross-sectional studies were rated ‘good’.10 11 32 33 37 38 41–44 Most studies did not assess the exposure more than once over time (7/10 studies).10 32 33 37 41–43 A smaller proportion was unable to demonstrate that the exposure of interest was measured before the outcome being measured (5/10 studies)10 11 38 41 44 or did not adjust models to include potential confounders to assess their impact on the relationship between exposure(s) and outcome(s) (3/10 studies).38 42 44 The reviewers were unable to find evidence in some studies if the outcome assessors were blinded to the exposure status of participants (3/10 studies)11 38 44 or whether there was a loss to follow-up among the cohort studies (3/5 studies).32 37 42 Among the case–control studies, four were rated as ‘good’,34–36 39 while one was rated as ‘fair’.40 The reviewers ascertained that some studies failed to provide a sample size justification (3/5 studies)34–36 or did not randomly select cases and/or controls from the eligible study population (2/5 studies).35 40
Supplemental material
Results of individual studies and syntheses
Nine outcomes were identified in the studies: hypertensive disorders of pregnancy (preeclampsia, severe preeclampsia, gestational hypertension and hypertensive disorders of pregnancy), blood transfusions, postpartum haemorrhage, disseminated intravascular coagulation (DIC), hysterectomy, ectopic pregnancy, uterine atony, placental abruption and SMM with mortality as a composite outcome. 26 risk factors were identified, 24 of these were individual risk factors, while 2 were community risk factors. No studies examined interpersonal/relationship or societal-level risk factors.
Online supplemental appendix 2 lists the frequency by which each risk factor and outcome were studied in the literature. A majority of studies examined ‘hypertensive disorders of pregnancy’ (8/15 studies)32–37 39 44 and ‘severe maternal morbidity and/or mortality’ (4/15 studies)10 11 41 43 as outcomes. A majority of studies examined body mass index (BMI) (6/15 studies),32–36 40 maternal age (6/15 studies),34–38 42 maternal race (5/15 studies)10 33 41–43 and parity (5/15 studies)34–36 40 42 as risk factors for various outcomes. Table 2 is a summary table that reports the number of studies grouped by outcome, the risk factors examined for associations and the direction of those associations. Online supplemental appendix 3 summarises additional details on study design, sample size and data sources, exposures and outcome variables, covariates, key findings, including the measures of effect, and study quality ratings.
Supplemental material
Summary of risk factors and outcomes by risk/association category*
Specific to hypertensive disorders of pregnancy, having a rural residency (1/1 studies), an overweight or obese BMI (4/5 studies), age above 35 years also referred to as ‘advanced maternal age’ (1/4 studies), and nulliparity (3/3 studies) was significantly associated with increased risk.32 34–36 44 Genetic predispositions to hypertensive disorders of pregnancy were not significantly associated with increased risk (3/3 studies).34–36 Studies that focused on SMMM identified being of Native American race (2/3 studies), having a physical health condition (1/1 study), a rural residency (1/2 studies) and births primarily paid by Medicaid (ie, public government insurance) (1/1 study) as significantly associated with increased risk. The risk of blood transfusions was significantly associated with Native American race (1/1 study), rural residency (2/2 studies) and Medicaid-funded births (1/1 study).10 11 41 Postpartum haemorrhage risk was significantly associated with being of Native American race when compared with other racial/ethnic groups, a gravidity≤5 and a birth weight of 4500 g, having a retained placenta, magnesium sulfate use (2/2 studies), antepartum bleeding, previous postpartum haemorrhage, being in the third-stage labour greater than 20 min, maternal rural residency, fetal macrosomia and oxytocin use for longer than 12 hours.40 42 Other outcomes are further described in online supplemental appendix 3.
This systematic review identified several factors related to maternal health among Native American women, including some that did not align with findings from other populations. For example, continuous smokeless tobacco use and cigarette smoking were found to have no significant association with pregnancy-induced hypertension in one study.39 A separate study identified that women under 35 had a decreased risk of hypertensive disorders of pregnancy compared with those older than 35.42 One study found no association between hypertensive disorders of pregnancy (eg, preeclampsia) and having an overweight/obese BMI.33 Genetic factors also demonstrated varying outcomes. One study identified that the CRP_B, rs1205 single-nucleotide polymorphisms (SNPs) (A allele dominant) were associated with a decreased risk for preeclampsia, while another study found the CRP rs3093068 SNP (G allele dominant) linked to an increased risk.34 35 Other SNPs examined in these studies showed no significant association with preeclampsia or other increased risk, while other SNPs showed no association or relationship.34 35 In contrast to other studies, Native American race and rural residency were not associated with SMM and/or mortality in three distinct studies.10 41 43 Another study found no significant association between uterine atony and factors, such as high gravidity, induction augmentation or chorioamnionitis. Interestingly, rural residency also did not appear to increase the risk of DIC.10 40 42
Reporting biases and certainty of evidence
All studies relied on administrative data sources to assess outcomes and exposures simultaneously, and all noted this as a considerable limitation in their study design. Four studies noted concerns with small sample sizes, missing exposure and outcome data and critical demographic information that may have led to misclassification bias. Two studies considered reporting bias in their study designs, while almost all studies (14/15 studies) referred to the misidentification of Native American women based on the predetermined guidelines for race designation.
Discussion
This systematic review synthesized the literature by conducting a broad search of outcomes associated with MMM and identifying their associated risk factors for Native American women in the USA. Despite the importance of understanding these outcomes for this population, we found a limited number of studies addressing these critical issues. All 15 studies identified risk factors at the individual level, suggesting that an overweight or obese BMI, advanced maternal age (35 years or older) in certain situations, parity and rural maternal residency are associated with Native American MMM. Few studies contradicted these findings and demonstrated no association with Native American race, rural maternal residency or advanced maternal age. One study found no association with hypertensive disorders of pregnancy, including pregnancy-induced hypertension, preeclampsia and severe preeclampsia with continuous smokeless tobacco use or continuous cigarette smoking.39
While advanced maternal age is often associated with higher risks for adverse maternal health outcomes in other populations, this review found both consistent and nuanced findings among Native American women. Specifically, advanced maternal age was associated with a higher risk of hypertensive disorders, including pregnancy-induced hypertension, especially among those who smoked during pregnancy. However, two studies found no significant association between age at delivery and preeclampsia in this population. These results suggest that, while advanced age can be a risk factor for some outcomes, such as hypertension, it may not uniformly affect all maternal health conditions. This could also indicate the presence of potential protective factors or differences in health profiles among Native American women that merit further investigation. Conversely, the higher risk of morbidities among public governmental health insurance (ie, Medicare or Medicaid) recipients is concerning and suggests a need for targeted interventions within this subgroup. Studies showed that rural Native American Medicaid-funded births had the highest adjusted rate of SMM and mortality, indicating potential disparities in healthcare quality and access.41 45
Studies assessing the relationship between genetic factors and preeclampsia or severe preeclampsia were completed in an Indian Reservation within a specific tribal health system.34–36 These studies uncovered that there were only two associations between genetic expression and preeclampsia for Native American women among those studies. These studies concurred that many of the risk factors, such as maternal age, nulliparity and obesity, that are associated with preeclampsia and severe preeclampsia in other populations were also operative in Native American communities.34–36
At the community level, our review identified four studies that included risk factors, such as maternal residency and the Indian Health Service Region. This limitation further indicates the need to expand research to identify and understand the role of community- and society-level risk factors. Social determinants of health, such as access to behavioural and primary care services, housing, crime and violence and health policies, have been demonstrated to contribute directly to MMM in more extensive population studies.46 Studies highlighted the higher incidence of SMM and mortality among rural Native American women compared with their urban counterparts, emphasising the critical impact of geographic and systemic disparities.10 40 42
This review did not find information on prenatal care utilisation and its association with MMM despite strong evidence supporting adequate prenatal care utilisation in culturally competent healthcare institutions.15 47 48 Early and adequate prenatal care is thought to promote healthy pregnancies through screening and managing a woman’s risk factors and health conditions and promote healthy behaviours during pregnancy.6
This review did not consider the effects of historical trauma, discrimination and racism, which are significant health determinants for Native Americans.17 These experiences contribute to health deterioration over time, as explained by the weathering hypothesis, which suggests that cumulative stress from racism and socioeconomic disadvantages leads to worse health outcomes.13
Appraisal
Most studies were rated as ‘good’ (14/15 studies), while one was rated as ‘fair’. Despite this, we were able to highlight the methodological shortcomings of some of the studies, such as the failure to assess the exposure more than once over time, the inability to demonstrate that exposure was measured before outcome measurement or not adjusting models to include potential confounders. Additionally, some studies failed to provide sample size justification or did not randomly select cases or controls from the eligible study population, posing bias risks.
We identified additional shortcomings in the available evidence. Racial/ethnic misclassification on administrative databases led to challenges with under-reporting and further affected the selection of study participants. Given the small percentage of Native American births in the USA, which is only 0.7%, minor errors in misclassification can significantly impact data analysis.49 Multiple studies in this review reported small sample sizes, making it difficult to determine if a particular outcome was a true finding, possibly allowing for type II errors. Among studies that included samples that were not fully Native American, most reported a Native American sample size of ≤1.4%. The limited research in these communities hinders the identification of additional risk factors for morbidity and mortality specific to Native American women.50 The measurement of MMM varied across the studies. This review used a broader definition of these outcomes, including conditions not listed by the CDC as SMM. This approach aimed to provide a complete understanding of the risk factors and health outcomes specific to Native American women. Finally, relying heavily on administrative data presents unique challenges in identifying risk factors not traditionally included in these datasets, as their primary purpose may not align with the study’s hypothesis.51
Strengths and limitations
Our systematic review faced some limitations despite our use of an expansive search strategy informed by other published reviews.3 52 We were unable to translate all MesH terms into indexed language for other databases. There is also a risk of publication bias and selective reporting of significant findings in the studies. Using NIHs quality assessment tools, which are not independently published nor standardised, may introduce bias due to the qualitative nature of the review. Despite this, other systematic reviews have built the evidence supporting the utility and practicality of using this tool.3 Furthermore, the review revealed significant variation in the risk factors and outcomes across different studies. This highlights the complexity and heterogeneity of maternal health issues among Native American women. This variation presents a challenge in drawing definitive conclusions.
Despite these limitations, this systematic review is one of the few that identifies risk factors for SMM and mortality among Native American women in the USA. The review addresses a critical gap in the literature by focusing on this historically marginalised and underserved population, providing valuable insights for targeted public health interventions and policies. Including various study designs allows for a more comprehensive understanding of the associated risk factors and outcomes. We comprehensively reviewed the current literature using multiple search strategies incorporating the CDCs list of procedural and diagnoses for SMM. This systematic review used recommended language to identify research in Native American communities following the National Library of Medicine Guidance.53 Rigorous quality assessment tools were employed to evaluate the methodological quality of the included studies, ensuring that the findings are based on reliable and valid evidence. Additionally, organising the identified risk factors into socioecological levels provides a structured approach to understanding the complex interplay of factors influencing maternal health in Native American communities.
Implications for practice, policy and future research
Our review demonstrates the lack of attention reflected in the scarcity of evidence available to understand this public health crisis among a population that is often ignored. The limited type of risk factors studied, the study designs, settings and outcomes limit the ability of healthcare and public health organisations to properly design and implement tailored approaches to reduce disparities in this community further. Public health initiatives must prioritise culturally competent care and address the unique challenges faced by Native American women to mitigate the risks of MMM. By acknowledging and addressing these gaps in the literature, public health can better inform policy, enhance clinical practices and ultimately improve health outcomes for Native American mothers and their families.
Data availability statement
All data relevant to the study are included in the article or uploaded as supplementary information. The original contributions presented in the study are included in the article’s supplemental material; further inquiries can be directed to the corresponding author.
Ethics statements
Patient consent for publication
Ethics approval
Not applicable.
Acknowledgments
We would like to express our gratitude to Jean McClelland for their invaluable consultation on the development of the search strategy, which greatly enhanced the quality of this review. We also extend our thanks to Laura Luna Bellucci for her support of this project and for her thorough review of the manuscript. Their contributions were instrumental to the success of this work.
References
Supplementary materials
Supplementary Data
This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content.
Footnotes
Contributors MC is responsible for the overall content as the guarantor. MC and PM developed the protocol objectives and design. MC wrote the protocol and is the submitting author under supervision of PM. MC developed the search strategy. AIZ, CR, AN and AA reviewed abstracts and full-text articles, extracted data from included studies and critically appraised the literature. AIZ and AN co-wrote the introduction, CR and AA co-wrote the methods, and MC wrote the remaining sections, including results and discussion. PM, JE, CH, SDP and VLN reviewed and made corrections to the manuscript on multiple occasions, leading to the final written manuscript.
Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Competing interests None declared.
Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting or dissemination plans of this research.
Provenance and peer review Not commissioned; externally peer reviewed.
Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.