Article Text

Continuity of care by a primary midwife (caseload midwifery): a cost analysis using results from the COSMOS randomised controlled trial
  1. Emily J Callander1,2,
  2. Hannah Jackson3,
  3. Helen L McLachlan4,5,
  4. Mary-Ann Davey6 and
  5. Della A Forster2,4
  1. 1 University of Technology Sydney, Sydney, New South Wales, Australia
  2. 2 The Royal Women’s Hospital, Melbourne, Victoria, Australia
  3. 3 Faculty of Health, University of Technology Sydney, Broadway, New South Wales, Australia
  4. 4 Judith Lumley Centre, La Trobe University, Melbourne, Victoria, Australia
  5. 5 School of Nursing and Midwifery, La Trobe University, Melbourne, Victoria, Australia
  6. 6 Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
  1. Correspondence to Dr Emily J Callander, University of Technology Sydney, Sydney, Australia; Emily.callander{at}uts.edu.au

Abstract

Introduction Caseload midwifery (continuity of midwifery carer) offers benefits including lower caesarean section rates, lower risks of preterm birth and stillbirth, and improved maternal satisfaction of care. Despite these advantages, concerns about additional costs hinder widespread implementation. This study examines the cost of caseload midwifery compared with standard maternity care from the perspective of both public hospitals and public funders.

Methods A cost analysis was conducted using data from a randomised controlled trial of 2314 low-risk pregnant women in Melbourne, Australia. Women randomised to caseload care received antenatal, intrapartum and postpartum care from a primary midwife, with some care provided by a ‘back-up’ midwife. Women in standard care received midwifery-led care with varying levels of continuity, junior obstetric care or community-based medical care. The cost analysis compared differences in mean costs of health resources to public hospitals and to public funders. Additionally, a budget impact analysis estimated total costs to the health system between 2023 and 2027.

Results For public hospitals, there was no significant difference in overall costs between women receiving caseload midwifery (n=1146) versus standard care (n=1151) ($A12 363 (SD: $A4967) vs $A12 323 (SD: $A7404); p=0.85). Conversely, public funders incurred lower expenditures for women receiving caseload midwifery ($A20 330 (SD: $A8312)) versus standard care ($A21 637 (SD: $A11 818); p <0.001). The budget impact analysis estimated savings of $A625 million to the health system over the next 5 years with expanded access to caseload midwifery in Australia.

Conclusion Caseload midwifery in low-risk women is cost-neutral to public hospitals and cost-saving to public funders.

Tweetable abstract Continuity of midwifery for low-risk women reduces costs to public funders, with no additional costs to hospitals.

  • Maternal Health
  • Obstetrics

Data availability statement

Data are available upon reasonable request. Data may be shared upon request in accordance with our ethics approvals.

https://creativecommons.org/licenses/by/4.0/

This is an open access article distributed in accordance with the Creative Commons Attribution 4.0 Unported (CC BY 4.0) license, which permits others to copy, redistribute, remix, transform and build upon this work for any purpose, provided the original work is properly cited, a link to the licence is given, and indication of whether changes were made. See https://creativecommons.org/licenses/by/4.0/.

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WHAT IS ALREADY KNOWN ON THIS TOPIC

  • Continuity of care by a primary midwife (caseload midwifery) is associated with beneficial health outcomes and increased rates of maternal satisfaction.

  • Despite positive effects, uncertainty regarding the economic consequences associated with this model of care remains a significant barrier to the uptake of this highly effective maternal health intervention.

WHAT THIS STUDY ADDS

  • To drive changes in the uptake of caseload midwifery, this study assessed the cost implications of caseload midwifery in comparison to standard maternity care from the perspective of both public hospitals and public funders.

HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY

  • Caseload midwifery was found to reduce costs to public funders for low-risk women without increasing costs for public hospitals.

Introduction

High-income countries are grappling with the concurrent challenges in maternity care of rapidly increasing intervention rates, particularly caesarean sections, and the imperative to prevent rare but catastrophic outcomes such as morbidity and death.1 2 This is set against a background of rapidly increasing healthcare costs and tightening government expenditure.3 Caesarean section is a high-cost medical procedure that comes with an increased risk of adverse outcomes.4 5 Consequently, reducing the need for caesarean section is an ongoing international priority.6

While high-income countries have very low rates of maternal and neonatal morbidity and mortality, some individual health services have recently been identified as service ‘failures’, with clusters of catastrophic adverse events.7–9 These incidents have highlighted the need for attention to maternal experience and maternal and neonatal safety.10 11 Furthermore, follow-up responses have also highlighted the need to prioritise the implementation of evidence-based responses both within these individual services, and across maternity care more broadly.12

Continuity of midwifery carer in women of low obstetric risk has been shown in the COmparing Standard Maternity care with One-to-one midwifery Support (COSMOS) randomised controlled trial (RCT) to reduce the risk of caesarean section, and admission to special or neonatal intensive care for the infant.13 The model, called ‘caseload midwifery’, where women received antenatal, intrapartum and postpartum care from a primary midwife, also resulted in an improvement in birth experience for women,14 15 and has been associated with lower risk of preterm birth, stillbirth and neonatal death.16 Other RCT evidence from all-risk women concluded that caseload midwifery is safe for women of any risk and produces cost savings for hospital funders.17 As such, increasing access to caseload midwifery should be a key strategy to concurrently address rising intervention rates, while improving experience and safety.

A key barrier to wider implementation or scale-up of caseload midwifery is the perceived additional costs to public hospitals associated with this model.18 Comprehensive evidence of the costs of caseload midwifery and standard care is thus needed in order to inform decision-making about establishment or scale-up. The objective of this study was to identify the cost and budget impact of caseload midwifery compared with standard care among women of low obstetric risk in Australia.

Methods

Study setting and location

In Australia, caesarean section rates were 37% in 2020, which is above the Organisation for Economic Co-operation and Development average.19 20 It is projected that 45% of births in Australia will be by caesarean section by 2030.21 Maternity care is funded through a mix of public funding, out-of-pocket fees and private health insurance funds.22 Public hospitals are funded jointly by both the federal and state governments through Public Hospital Funding Agreements on an activity-based funding model. Each episode of inpatient, outpatient and emergency department care in public hospitals is funded at a set rate determined by the Independent Hospital Pricing Authority, with no out-of-pocket fees for Medicare-eligible patients.23 Any care provided outside of public hospitals is partly subsidised through a different pool, Medicare, which is funded solely by the federal government.

Public hospitals are owned and managed by state governments, with individual hospitals being operated by a board and executive responsible for the provision of services and financial sustainability. Once government funding reaches a hospital, the hospital is then responsible for providing the care, including payment of staff, consumables and facility costs. This includes midwife and medical salaries associated with providing maternity care. Caseload midwifery in Australia is designed for implementation in the public hospital setting. As such, it will have cost implications to public funders as it will affect the types of activities or episodes of care being funded, and to individual hospitals as it involves different staff, consumable and facility costs.

Study population

COSMOS was a two-arm RCT designed to compare caseload midwifery to standard maternity care in women at low risk of obstetric complications. The trial design is described in detail elsewhere.13 24 Briefly, women at low risk of obstetric complications were recruited at the Royal Women’s Hospital, a public tertiary women’s hospital in Melbourne, Australia, between September 2007 and June 2010. Women were eligible for inclusion in the trial if they were able to speak, read and write English, if they had a singleton pregnancy of less than 24 weeks gestation at recruitment and if they were considered low obstetric risk, with no complications during the current pregnancy and no precluding medical conditions (eg, cardiac disease, diabetes, epilepsy, substance use, obesity or significantly underweight). Women with a previous caesarean section were excluded. Caseload midwifery was not available to women outside the trial.

Comparators

Caseload midwifery care

Women randomised to the intervention group received the majority of their antenatal, intrapartum and postnatal care from a primary caseload midwife at the hospital. If complications arose, the primary midwife collaborated with other health professionals (eg, obstetricians) while continuing to provide caseload care. Caseload midwives provided ‘back-up’ care for each other, so that if a caseload midwife was sick, on personal leave or unavailable the back-up midwife would provide care for a woman. Women saw an obstetrician at booking, at 36 weeks of gestation and if the pregnancy lasted beyond 40 weeks’ gestation. Intrapartum care was provided in the birth suite by the caseload midwife (89% of the time), or otherwise by a core hospital midwife. Postpartum, the caseload midwife saw women on most days in hospital to provide postnatal care and provided domiciliary care following discharge from hospital. All care was provided according to hospital guidelines and protocols. Full-time midwives had a caseload of 45 women per annum.

Standard maternity care

Women randomised to the control group could choose from the standard hospital options for low-risk women (referred to as ‘standard care’). These included midwifery-led care (78%), which generally meant that women saw a different midwife at each visit, based on who was rostered to work at the time of care; obstetric trainee care (2%); or shared care where antenatal care is shared between an accredited general medical practitioner (GP) and the hospital (15%). Five per cent transferred their care elsewhere. As with caseload midwifery care, women in the standard care model saw an obstetrician at booking, and 36 weeks’ gestation and at 41 weeks’ gestation if required. Care was provided according to the same hospital guidelines and protocols as women in the caseload midwifery arm.

Study design: cost analysis

We conducted a cost analysis using data from the COSMOS RCT to determine if there are differences in cost between caseload midwifery and standard care for individual public hospitals providing care, and public funders.

Time horizon, discount rate

The time horizon for the cost analysis was from booking at around 16 weeks’ gestation, through to 2 months post partum. Since the follow-up period was less than 12 months, discounting of costs was not required.

Measurement and valuation of resources

Public hospital costs

Use of public hospital resources was identified from a combination of self-reported health service use from a survey administered to women at 2 months post partum, data collected from hospital records by the study team and administrative data. Health resources were costed from the hospital’s perspective. These are described in detail in online supplemental appendix 1.

Supplemental material

Expenditure by public funders

Expenditure by public funders was based on all episodes of care, also identified from self-reported health service use survey data administered to women at 2 months post partum, data collected from hospital records by the study team and administrative data. Funding per activity was based on the Independent Hospital Pricing Authority National Efficient Price Determination for 2022/2023,25 with the Inlier weight per activity multiplied by the National Efficient Price.25 These are described in detail in online supplemental appendix 1.

Study design: budget impact analysis

The second analysis was a budget impact analysis including costs to the health system, comprising both public hospital costs and expenditure by public funders for caseload midwifery and standard care in women at low risk of obstetric complications. This was designed to capture the cost implications of hypothetical national implementation. We assumed that uptake of caseload would be 70% in women at low risk of obstetric complications, and that adherence would be 90%; this was considered more reflective of potential use in practice. The analysis was designed to represent the Australian population of births between 2023 and 2027. Full methodological details are provided in online supplemental appendix 2.

Time horizon

The model took a 5-year time horizon, including all births and considering costs and outcomes between 2023 and 2027 (ie, for births in 2023 costs and outcomes will be considered for up to 5 years post partum, whereas those born in 2026 will only have costs and outcomes considered up to 1 year post partum). No discounting was applied.

Currency, price date and conversion

All costs are presented in 2021/2022 Australia dollars. For reference, at time of writing 1 Australian dollar is equal to 0.56 Pounds sterling, 0.63 Euros and 0.67 United States Dollars. When unit prices and funding amounts were not recorded in the original source in this price date, they were adjusted for inflation using the Reserve Bank of Australia inflation figures.26

Data analysis

Data were analysed on an intention-to-treat basis. Demographic characteristics of women receiving caseload midwifery and standard care were compared. Differences between groups were calculated using Pearson’s χ2 test, and Student’s t-test (p values reported). The average number of, or frequency of access to, different resources was then compared, followed by costs to public hospitals and expenditure by public funders. A supplementary analysis was conducted that compared costs to public hospitals and expenditure by public hospitals for women receiving shared care (with a GP). For costs, generalised linear models were used to compare differences, with a gamma distribution and log link function to account for the skewed nature of the cost data. Health service use was analysed as count data with negative binomial distribution. All analysis was conducted using SAS V.9.4.

Results

There were 1146 women allocated to caseload care and 1151 women allocated to standard care. Of the 1151 women allocated to standard care, 79.7% (917/1151) received public antenatal care with either midwives or obstetric trainees; 15.1% (174/1151) received shared care (with a GP); and 5.2% (60/1151) transferred to care elsewhere. Of the 1146 women allocated to caseload care, 3.3% (38/1146) received other care either at the Royal Women’s Hospital, or at a facility outside of Melbourne due to relocation. Table 1 demonstrates that the two groups were similar in terms of demographic characteristics.

Table 1

Demographic characteristics of women receiving caseload and standard care

In terms of health resources used, women allocated to caseload midwifery accessed slightly more antenatal midwife appointments (6.7 vs 6.1; p <0.001) but were less likely to have an epidural (28.3% vs 30.8%; p =0.04) than women in the standard care group. They also were less likely to have a caesarean section birth (19.3% vs 24.8%; p =0.001), had a shorter length of labour (12.9 hours vs 14.0 hours; p =0.04), and a shorter postnatal ward stay (55.5 hours vs 60.2 hours; p <0.001). The babies of women allocated to caseload midwifery had fewer admissions to special care nursery (SCN) or neonatal intensive care unit (NICU) (5.9% vs 9.2%; p=0.002) and had shorter lengths of stay post birth (68.2 hours vs 73.9 hours; p <0.001). Women in the caseload group also had slightly more postnatal home visits (2.1 visits vs 1.7 visits; p <0.001) (table 2).

Table 2

Health service use of women

Based on annual caseload midwife salary and a caseload of 45 women, caseload midwives cost public hospitals $A3414 per woman to provide care through the antenatal, intrapartum and postnatal time period. Women receiving caseload midwifery had lower mean costs associated with antenatal visits (which includes non-caseload midwife, obstetrician and GP time) ($A214 vs $A316; p <0.001), epidural use ($A94 vs $A110; p =0.04), birth suite ($A1376 vs $A3,729; p <0.001) and postnatal ward costs for mother ($A2993 vs $A3239; p <0.001) and baby ($A3731 vs $A4154; p <0.001). Women receiving caseload care had $A0 for postnatal costs after discharge as these costs were included in caseload midwife salary costs. There was no significant difference in overall costs between women allocated to the caseload group compared with women allocated to standard care ($A12 363 vs $A12,323; p=0.85) (table 3). There was also no significant difference in costs per woman for public hospitals for women receiving shared care (with a GP), and women receiving caseload midwifery (online supplemental appendix 3). In the scenario analysis where women received intrapartum care from their caseload or back-up midwife and the rostered hospital midwives as well, costs were $A1971 higher for women receiving caseload midwifery (online supplemental appendix 4).

Table 3

Mean costs to public hospitals per woman

Expenditure by public funders on midwife antenatal outpatient episodes ($A1380 vs $A1260; p <0.001) and obstetrician antenatal outpatient episodes ($A597 vs $A583; p=0.01) was higher for women receiving caseload midwifery care compared with women receiving standard care (table 4). In contrast, expenditure by public funders on labour, birth and postnatal inpatient episodes of care was lower for women receiving caseload midwifery care compared with women receiving standard care ($A17 521 vs $A18 967; p <0.001). In all, expenditure by public funders was $A1307 less for women receiving caseload midwifery than women receiving standard care (p <0.001).

Table 4

Expenditure by public funders per woman

The modelled budget impact analysis (table 5) shows the overall cost implications of caseload midwifery compared with standard care for low-risk women in Australia, with hypothetical nationwide implementation. The overall number of eligible women (women of low obstetric risk, giving birth in a public hospital) is expected to initially rise, due to the increasing proportion of women giving birth in public hospitals, and then decline due to the decreasing proportion of women considered to be low obstetric risk. There would be net cost savings of $A132 million to the public health system in year 1 (2023), and $A115 million in year 5 (2027). Overall, there would be savings of $A625 million to the health system over the next 5 years if 70% eligible women had access to caseload midwifery in Australia, with 90% adherence.

Table 5

Modelled budget impact analysis of caseload midwifery compared with standard care, assuming 70% uptake rate and 90% adherence

Discussion

Main findings

Caseload midwifery for women at low obstetric risk was not associated with increased overall costs to public hospitals ($A12 363 for women receiving caseload; $A12 323 for women receiving standard care). Caseload midwifery was associated with a reduction in expenditure to public funders of $A1307 per woman compared with standard care. This was primarily by lower use of epidural, caesarean section, instrumental vaginal birth, fewer special care nursery and neonatal intensive care unit admissions, and shorter length of labour and length of stay post birth for women receiving caseload midwifery compared with standard care. The lower use of these resources, and thus lower costs to public hospitals, offset the additional staffing costs for midwife and obstetric time. When considered at the national level from a health systems perspective (considering both costs to public hospitals and expenditure by public funders), caseload midwifery is cost saving. If implemented at a national level in Australia, caseload midwifery for low-risk women could save the system $A625 million over the next 5 years.

Strengths and limitations

The primary limitation of the study was that it was based on a single site, in an urban setting with strong leadership. This may mean that the findings may be different to those seen with wider implementation. Previous studies from this trial13 have noted some differences in the characteristics of women participating in the trial compared with the overall population, notably the higher proportion of women who were married or living with their partner, nulliparous women and women born overseas. The key strength of this study is that it is based on results directly collected during an RCT and thus represents a balanced comparison between study groups. Furthermore, the study took a comprehensive approach to cost measurement, capturing both public hospital costs and expenditure by public funders.

Interpretation

Few studies have assessed the costs of caseload midwifery relative to standard care, and the limited evidence base on costs of caseload midwifery is still considered a barrier to implementation. The M@NGO RCT of all risk women found cost savings to hospital funders associated with the birth event for women receiving caseload midwifery, compared with standard care.17 A Cochrane review16 published in 2016 compared midwife-led continuity of care models with other models of care and found a trend towards cost-saving for midwife-led continuity of care models. More recently, an observational study from Australia comparing the real-world costs of caseload midwifery and standard care demonstrated cost-savings of AU$A5208 per woman in the caseload model from the public funder’s perspective; however, this is related to all-risk women.27 Two modelling studies have also been conducted—one study from the USA demonstrated that a shift from obstetric-led to midwife-led care could be cost saving for low-risk pregnancies28 and another Australian study identified that caseload midwifery in low-risk nulliparous women was cost-saving compared with standard care.29 However, none of these previous studies have considered staffing costs to public hospitals.

Our study also highlighted a number of important factors that need to be considered as a part of implementation to ensure financial sustainability. First, when considering only midwifery staffing costs, caseload midwifery is higher cost than standard care. It is also higher cost when the caseload midwife and rostered hospital midwives both provide intrapartum care. Cost savings to public hospitals are seen through a small reduction in obstetric staff time but also through a reduction in costs of anaesthetists for epidurals and caesarean sections, theatre costs for providing caesarean section, SCN and NICU admissions. Thus, for implementation within public hospitals, there would need to be a redistribution of cost savings from other areas into midwifery salary to support the additional midwifery staffing costs required for caseload midwifery. Another crucial finding from this study is that caseload midwifery will result in higher costs to public hospital funders if the number of midwives rostered to birth suite to provide standard care is not proportionately reduced with caseload midwifery.

Our findings that demonstrated substantial cost savings for public hospital funders are also an important consideration for implementation. The cost-saving per woman receiving caseload midwifery to public funders ($A1307 per woman) is larger than the potential additional staffing costs for midwives incurred by public hospitals ($A624 per woman). From a policy perspective, public hospital funders (in Australia, state and Federal governments) could fund individual hospitals to support start-up costs of caseload midwifery, given the previously noted need for hospitals to internally redistribute staff savings and reduce birth suite midwives providing standard care. This could still be cost saving to public funders given the reduction in expenditure associated with reduced numbers of caesarean section births, reduction in length of stay in birth suite and postnatal ward, and fewer neonatal admission to special care.

Conclusion

Among low-risk women, caseload midwifery is not associated with increased costs to public hospitals compared with standard care, and significantly reduces costs to public funders. Overall, to health systems, caseload midwifery reduces costs compared with standard care in low-risk women and could result in substantial cost savings if fully implemented.

Supplemental material

Data availability statement

Data are available upon reasonable request. Data may be shared upon request in accordance with our ethics approvals.

Ethics statements

Patient consent for publication

Ethics approval

Ethics approval was obtained from the Royal Women’s Hospital (07/01) and La Trobe University Human Research Ethics Committees (07/04). Participants gave informed consent to participate in the study before taking part.

Acknowledgments

We gratefully acknowledge the National Health and Medical Research Council for trial funding, the women and midwives who participated in the study, other members of the research team, and members of the study Reference Group, the Safety Committee, and the Data Monitoring Committee. We acknowledge the dedicated research midwives and research assistants and the support of the study by hospital management, midwifery, and obstetric teams, as well as the Information Technology Department and Health Information Services. We also acknowledge Associate Professor Lisa Gold and Ms Bree Rankin for the health economic data collection design.

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

  • Presented at Preliminary results from this study were presented at the Perinatal Society of Australia and New Zealand 2023 Conference.

  • Contributors HLM, M-AD and DAF originally conceived the study and contributed to the initial grant application. EJC led the design of, and conducted, the cost data analysis and led the drafting of the manuscript. HJ contributed to data analysis. All authors contributed to the analysis design, interpretation of the results and made contributions to subsequent drafts. All authors had full access to the data, and all read and approved the final manuscript. EC acts as guarantor.

  • Funding Funding was received from the Australian National Health and Medical Research Council (Project Grant Number: 433040).

  • Competing interests None declared.

  • Patient and public involvement Patients and/or the public were involved in the design, or conduct, or reporting, or dissemination plans of this research. Refer to the Methods section for further details.

  • 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.