Download PDF
Am J Perinatol
DOI: 10.1055/a-2223-3520
Original Article

Trends and Disparities in Severe Maternal Morbidity Indicator Categories during Childbirth Hospitalization in California from 1997 to 2017

Alison M. El Ayadi 
1   Department of Obstetrics, Gynecology and Reproductive Sciences, Department of Epidemiology and Biostatistics, University of California, San Francisco, California
,
Audrey Lyndon 
2   NYU Rory Meyers College of Nursing, New York, New York
,
Peiyi Kan
3   Department of Pediatrics, Stanford University School of Medicine, Stanford, California
,
Mahasin S. Mujahid
4   Division of Epidemiology, School of Public Health, University of California Berkeley, Berkeley, California
,
Stephanie A. Leonard
5   Department of Obstetrics and Gynecology, Dunlevie Maternal-Fetal Medicine Center, Stanford University School of Medicine, Stanford, California
,
Elliott K. Main
5   Department of Obstetrics and Gynecology, Dunlevie Maternal-Fetal Medicine Center, Stanford University School of Medicine, Stanford, California
,
Suzan L. Carmichael
6   Department of Pediatrics, Department of Obstetrics and Gynecology, Stanford University, Stanford, California
› Author Affiliations Funding This study was funded by the National Institute of Nursing Research Grant R01NR017020 (PI: S.L.C.). The funders had no role in study design; collection, analysis, and interpretation of data; writing the report; and in the decision to submit the article for publication.
› Further Information
    Permissions and Reprints

Abstract

Objective Severe maternal morbidity (SMM) is increasing and characterized by substantial racial and ethnic disparities. Analyzing trends and disparities across time by etiologic or organ system groups instead of an aggregated index may inform specific, actionable pathways to equitable care. We explored trends and racial and ethnic disparities in seven SMM categories at childbirth hospitalization.

Study Design We analyzed California birth cohort data on all live and stillbirths ≥ 20 weeks' gestation from 1997 to 2017 (n = 10,580,096) using the Centers for Disease Control and Prevention's SMM index. Cases were categorized into seven nonmutually exclusive indicator categories (cardiac, renal, respiratory, hemorrhage, sepsis, other obstetric, and other medical SMM). We compared prevalence and trends in SMM indicator categories overall and by racial and ethnic group using logistic and linear regression.

Results SMM occurred in 1.16% of births and nontransfusion SMM in 0.54%. Hemorrhage SMM occurred most frequently (27 per 10,000 births), followed by other obstetric (11), respiratory (7), and sepsis, cardiac, and renal SMM (5). Hemorrhage, renal, respiratory, and sepsis SMM increased over time for all racial and ethnic groups. The largest disparities were for Black individuals, including over 3-fold increased odds of other medical SMM. Renal and sepsis morbidity had the largest relative increases over time (717 and 544%). Sepsis and hemorrhage SMM had the largest absolute changes over time (17 per 10,000 increase). Disparities increased over time for respiratory SMM among Black, U.S.-born Hispanic, and non-U.S.-born Hispanic individuals and for sepsis SMM among Asian or Pacific Islander individuals. Disparities decreased over time for sepsis SMM among Black individuals yet remained substantial.

Conclusion Our research further supports the critical need to address SMM and disparities as a significant public health priority in the United States and suggests that examining SMM subgroups may reveal helpful nuance for understanding trends, disparities, and potential needs for intervention.

Key Points

  • By SMM subgroup, trends and racial and ethnic disparities varied yet Black individuals consistently had highest rates.

  • Hemorrhage, renal, respiratory, and sepsis SMM significantly increased over time.

  • Disparities increased for respiratory SMM among Black, U.S.-born Hispanic and non-U.S.-born Hispanic individuals and for sepsis SMM among Asian or Pacific Islander individuals.

Keywords

health equity - racial and ethnic disparities - severe maternal morbidity - maternal health - pregnancy complications - obstetric complications

Authors' Contributions

A.M.E. played a key role in conceptualization, formal analysis, investigation, methodology, visualization, and contributed to both the original draft and the subsequent review and editing. A.L. contributed significantly to conceptualization, investigation, methodology, and was involved in both the original draft and review and editing stages, providing supervision. P.K. took on responsibilities in data curation, formal analysis, investigation, methodology, visualization, and participated in writing—both the original draft and the review and editing process. M.S.M. focused on writing and reviewing. S.A.L. participated in the writing and reviewing stages. E.K.M. played a vital role in conceptualization, methodology, and contributed to the review and editing. S.L.C. took on multiple roles, including conceptualization, data curation, investigation, funding acquisition, methodology, resources, writing—both original draft and review/editing, supervision, project administration, and additional funding acquisition.


Supplementary Material



Publication History

Received: 03 September 2023

Accepted: 04 December 2023

Accepted Manuscript online:
06 December 2023

Article published online:
29 January 2024

© 2024. Thieme. All rights reserved.

Thieme Medical Publishers, Inc.
333 Seventh Avenue, 18th Floor, New York, NY 10001, USA

 

  • References

  • 1 Kilpatrick SK, Ecker JL. American College of Obstetricians and Gynecologists and the Society for Maternal–Fetal Medicine. Severe maternal morbidity: screening and review. Am J Obstet Gynecol 2016; 215 (03) B17-B22
    Google Scholar
  • 2 Geller SE, Koch AR, Garland CE, MacDonald EJ, Storey F, Lawton B. A global view of severe maternal morbidity: moving beyond maternal mortality. Reprod Health 2018; 15 (Suppl. 01) 98
    Google Scholar
  • 3 Centers for Disease Control and Prevention. Severe maternal morbidity in the United States. Accessed March 10, 2019 at: https://www.cdc.gov/reproductivehealth/maternalinfanthealth/severematernalmorbidity.html
    Google Scholar
  • 4 Hirai AH, Owens PL, Reid LD, Vladutiu CJ, Main EK. Trends in severe maternal morbidity in the us across the transition to ICD-10-CM/PCS from 2012-2019. JAMA Netw Open 2022; 5 (07) e2222966-e2222966
    Google Scholar
  • 5 Creanga AA, Berg CJ, Syverson C, Seed K, Bruce FC, Callaghan WM. Race, ethnicity, and nativity differentials in pregnancy-related mortality in the United States: 1993-2006. Obstet Gynecol 2012; 120 (2 Pt 1): 261-268
    Google Scholar
  • 6 ACOG Committee Opinion No. ACOG Committee Opinion No. 649: racial and ethnic disparities in obstetrics and gynecology. Obstet Gynecol 2015; 126 (06) e130-e134
    Google Scholar
  • 7 Holdt Somer SJ, Sinkey RG, Bryant AS. Epidemiology of racial/ethnic disparities in severe maternal morbidity and mortality. Semin Perinatol 2017; 41 (05) 258-265
    Google Scholar
  • 8 Admon LK, Winkelman TNA, Zivin K, Terplan M, Mhyre JM, Dalton VK. Racial and ethnic disparities in the incidence of severe maternal morbidity in the United States, 2012-2015. Obstet Gynecol 2018; 132 (05) 1158-1166
    Google Scholar
  • 9 Leonard SA, Main EK, Scott KA, Profit J, Carmichael SL. Racial and ethnic disparities in severe maternal morbidity prevalence and trends. Ann Epidemiol 2019; 33: 30-36
    Google Scholar
  • 10 Creanga AA, Bateman BT, Kuklina EV, Callaghan WM. Racial and ethnic disparities in severe maternal morbidity: a multistate analysis, 2008-2010. Am J Obstet Gynecol 2014; 210 (05) 435.e1-435.e8
    Google Scholar
  • 11 Eichelberger KY, Doll K, Ekpo GE, Zerden ML. Black lives matter: claiming a space for evidence-based outrage in obstetrics and gynecology. Am J Public Health 2016; 106 (10) 1771-1772
    Google Scholar
  • 12 Jain JA, Temming LA, D'Alton ME. et al. SMFM special report: putting the “M” back in MFM: reducing racial and ethnic disparities in maternal morbidity and mortality: a call to action. Am J Obstet Gynecol 2018; 218 (02) B9-B17
    Google Scholar
  • 13 Martin JA, Hamilton BE, Osterman MJ, Driscoll AK, Mathews TJ. Births: final data for 2015. Natl Vital Stat Rep 2017; 66 (01) 1
    Google Scholar
  • 14 Carr RC, McKinney DN, Cherry AL, Defranco EA. Maternal age-specific drivers of severe maternal morbidity. Am J Obstet Gynecol MFM 2022; 4 (02) 100529
    Google Scholar
  • 15 Caughey AB. Prepregnancy obesity and severe maternal morbidity: What can be done?. JAMA 2017; 318 (18) 1765-1766
    Google Scholar
  • 16 Metcalfe A, Wick J, Ronksley P. Racial disparities in comorbidity and severe maternal morbidity/mortality in the United States: an analysis of temporal trends. Acta Obstet Gynecol Scand 2018; 97 (01) 89-96
    Google Scholar
  • 17 Mhyre JM, Bateman BT, Leffert LR. Influence of patient comorbidities on the risk of near-miss maternal morbidity or mortality. Anesthesiology 2011; 115 (05) 963-972
    Google Scholar
  • 18 Leonard SA, Main EK, Carmichael SL. The contribution of maternal characteristics and cesarean delivery to an increasing trend of severe maternal morbidity. BMC Pregnancy Childbirth 2019; 19 (01) 16
    Google Scholar
  • 19 Kuklina EV, Meikle SF, Jamieson DJ. et al. Severe obstetric morbidity in the United States: 1998-2005. Obstet Gynecol 2009; 113 (2 Pt 1): 293-299
    Google Scholar
  • 20 Howell EA, Egorova N, Balbierz A, Zeitlin J, Hebert PL. Black-white differences in severe maternal morbidity and site of care. Am J Obstet Gynecol 2016; 214 (01) 122.e1-1 -22.e7
    Google Scholar
  • 21 Howell EA, Egorova NN, Balbierz A, Zeitlin J, Hebert PL. Site of delivery contribution to black-white severe maternal morbidity disparity. Am J Obstet Gynecol 2016; 215 (02) 143-152
    Google Scholar
  • 22 Howell EA, Zeitlin J. Improving hospital quality to reduce disparities in severe maternal morbidity and mortality. Semin Perinatol 2017; 41 (05) 266-272
    Google Scholar
  • 23 Fingar KR, Hambrick MM, Heslin KC, Moore JC. Trends and disparities in delivery hospitalizations involving severe maternal morbidity,. 2006–2015. HCUP Statistical Brief #243. 2018 . Accessed April 01, 2023 at: www.hcup-us.ahrq.gov/reports/statbriefs/sb243-Severe-Maternal-Morbidity-Delivery-Trends-Disparities.pdf
    Google Scholar
  • 24 Gray KE, Wallace ER, Nelson KR, Reed SD, Schiff MA. Population-based study of risk factors for severe maternal morbidity. Paediatr Perinat Epidemiol 2012; 26 (06) 506-514
    Google Scholar
  • 25 Lindquist A, Noor N, Sullivan E, Knight M. The impact of socioeconomic position on severe maternal morbidity outcomes among women in Australia: a national case-control study. BJOG 2015; 122 (12) 1601-1609
    Google Scholar
  • 26 Main EK, Abreo A, McNulty J. et al. Measuring severe maternal morbidity: validation of potential measures. Am J Obstet Gynecol 2016; 214 (05) 643.e1-643.e10
    Google Scholar
  • 27 Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention. Severe maternal morbidity indicators and corresponding ICD codes during delivery hospitalizations. Centers for Disease Control and Prevention. Accessed May 5, 2018 at: https://www.cdc.gov/reproductivehealth/maternalinfanthealth/smm/severe-morbidity-ICD.htm
    Google Scholar
  • 28 Snowden JM, Klebanoff MA. Accurate identification of cohort study designs in perinatal research: a practical guide. Am J Obstet Gynecol 2022; 227 (02) 231-235.e1
    Google Scholar
  • 29 Danielsen BH, Carmichael SL, Gould JB, Lee HC. Linked birth cohort files for perinatal health research: California as a model for methodology and implementation. Ann Epidemiol 2023; 79: 10-18
    Google Scholar
  • 30 Centers for Disease Control and Prevention. Severe maternal morbidity indicators and corresponding ICD-9-CM/ICD-10-CM/PCS codes during delivery hospitalizations. 2019 . Accessed February 1, 2018 at: https://www.cdc.gov/reproductivehealth/maternalinfanthealth/smm/severe-morbidity-ICD.htm
    Google Scholar
  • 31 Williams DR, Sternthal M. Understanding racial-ethnic disparities in health: sociological contributions. J Health Soc Behav 2010; 51 (suppl, suppl): S15-S27
    Google Scholar
  • 32 Office of Management and Budget. Revisions to the standards for the classification of federal data on race and ethnicity. Fed Regist October 30, 1997;62(210)
    Google Scholar
  • 33 Associated Press. Why we will lowercase white. Accessed July 20, 2020 at: https://blog.ap.org/announcements/why-we-will-lowercase-white#:~:text=AP%20style%20will%20continue%20to,capitalize%20Black%20in%20such%20uses
    Google Scholar
  • 34 Moseson H, Zazanis N, Goldberg E. et al. The imperative for transgender and gender nonbinary inclusion: beyond women's health. Obstet Gynecol 2020; 135 (05) 1059-1068
    Google Scholar
  • 35 Alliance BWSatRWGotBMM. Black maternal health research re-envisionsed: best practices for the conduct of research with, for, and by Black Mamas. Harv Law Policy Rev 2020; 14: 393-415
    Google Scholar
  • 36 Lyndon A, Baer RJ, Gay CL, El Ayadi AM, Lee HC, Jelliffe-Pawlowski L. A population-based study to identify the prevalence and correlates of the dual burden of severe maternal morbidity and preterm birth in California. J Matern Fetal Neonatal Med 2021; 34 (08) 1198-1206
    Google Scholar
  • 37 Vesco KK, Ferrante S, Chen Y, Rhodes T, Black CM, Allen-Ramey F. Costs of severe maternal morbidity during pregnancy in us commercially insured and Medicaid populations: an observational study. Matern Child Health J 2020; 24 (01) 30-38
    Google Scholar
  • 38 Black CM, Vesco KK, Mehta V, Ohman-Strickland P, Demissie K, Schneider D. Costs of severe maternal morbidity in U.S. commercially insured and Medicaid populations: an updated analysis. Womens Health Rep (New Rochelle) 2021; 2 (01) 443-451
    Google Scholar
  • 39 O'Neil S, Platt I, Vohra D. et al. The high costs of maternal morbidity show why we need greater investment in maternal health. 2021 . Accessed at: https://www.commonwealthfund.org/publications/issue-briefs/2021/nov/high-costs-maternal-morbidity-need-investment-maternal-health
    Google Scholar
  • 40 Moran PS, Wuytack F, Turner M. et al. Economic burden of maternal morbidity - a systematic review of cost-of-illness studies. PLoS One 2020; 15 (01) e0227377
    Google Scholar
  • 41 Hailu EM, Carmichael SL, Berkowitz RL. et al. Racial/ethnic disparities in severe maternal morbidity: an intersectional lifecourse approach. Ann N Y Acad Sci 2022; 1518 (01) 239-248
    Google Scholar
  • 42 Luke AA, Huang K, Lindley KJ, Carter EB, Joynt Maddox KE. Severe maternal morbidity, race, and rurality: trends using the national inpatient sample, 2012-2017. J Womens Health (Larchmt) 2021; 30 (06) 837-847
    Google Scholar
  • 43 Callaghan WM, Creanga AA, Kuklina EV. Severe maternal morbidity among delivery and postpartum hospitalizations in the United States. Obstet Gynecol 2012; 120 (05) 1029-1036
    Google Scholar
  • 44 Hoyert DL, Miniño AM. Maternal mortality in the United States: changes in coding, publication, and data release, 2018. Natl Vital Stat Rep 2020; 69 (02) 1-18
    Google Scholar
  • 45 Collier AY, Molina RL. Maternal mortality in the United States: updates on trends, causes, and solutions. Neoreviews 2019; 20 (10) e561-e574
    Google Scholar
  • 46 Grodzinsky A, Schmidt L. Cardiovascular contribution to maternal mortality. Cardiol Clin 2021; 39 (01) 1-5
    Google Scholar
  • 47 Howell EA. Reducing disparities in severe maternal morbidity and mortality. Clin Obstet Gynecol 2018; 61 (02) 387-399
    Google Scholar
  • 48 Crear-Perry J, Correa-de-Araujo R, Lewis Johnson T, McLemore MR, Neilson E, Wallace M. Social and structural determinants of health inequities in maternal health. J Womens Health (Larchmt) 2021; 30 (02) 230-235
    Google Scholar
  • 49 Leonard SA, Kennedy CJ, Carmichael SL, Lyell DJ, Main EK. An expanded obstetric comorbidity scoring system for predicting severe maternal morbidity. Obstet Gynecol 2020; 136 (03) 440-449
    Google Scholar
  • 50 Kanu FA, Hamner HC, Scanlon KS, Sharma AJ. Anemia among pregnant women participating in the special supplemental nutrition program for women, infants, and children - United States, 2008-2018. MMWR Morb Mortal Wkly Rep 2022; 71 (25) 813-819
    Google Scholar
  • 51 Harrison RK, Lauhon SR, Colvin ZA, McIntosh JJ. Maternal anemia and severe maternal morbidity in a US cohort. Am J Obstet Gynecol MFM 2021; 3 (05) 100395
    Google Scholar
  • 52 Omotayo MO, Abioye AI, Kuyebi M, Eke AC. Prenatal anemia and postpartum hemorrhage risk: a systematic review and meta-analysis. J Obstet Gynaecol Res 2021; 47 (08) 2565-2576
    Google Scholar
  • 53 Mei Z, Cogswell ME, Looker AC. et al. Assessment of iron status in US pregnant women from the National Health and Nutrition Examination Survey (NHANES), 1999-2006. Am J Clin Nutr 2011; 93 (06) 1312-1320
    Google Scholar
  • 54 Al Khalaf SY, O'Reilly ÉJ, Barrett PM. et al. Impact of chronic hypertension and antihypertensive treatment on adverse perinatal outcomes: systematic review and meta-analysis. J Am Heart Assoc 2021; 10 (09) e018494
    Google Scholar
  • 55 Seely EW, Ecker J. Chronic hypertension in pregnancy. Circulation 2014; 129 (11) 1254-1261
    Google Scholar
  • 56 Lueth AJ, Allshouse AA, Blue NM. et al; National Institutes of Health (NIH), Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be (nuMoM2b), and National Heart, Lung, and Blood Institute (NHLBI) nuMoM2b Heart Health Study (nuMoM2b-HHS). Allostatic load and adverse pregnancy outcomes. Obstet Gynecol 2022; 140 (06) 974-982
    Google Scholar
  • 57 Davis D-A. Obstetric racism: the racial politics of pregnancy, labor, and birthing. Med Anthropol 2019; 38 (07) 560-573
    Google Scholar
  • 58 Sutton MY, Anachebe NF, Lee R, Skanes H. Racial and ethnic disparities in reproductive health services and outcomes, 2020. Obstet Gynecol 2021; 137 (02) 225-233
    Google Scholar
  • 59 Alhusen JL, Bower KM, Epstein E, Sharps P. Racial discrimination and adverse birth outcomes: an integrative review. J Midwifery Womens Health 2016; 61 (06) 707-720
    Google Scholar
  • 60 Main EK, Chang SC, Dhurjati R, Cape V, Profit J, Gould JB. Reduction in racial disparities in severe maternal morbidity from hemorrhage in a large-scale quality improvement collaborative. Am J Obstet Gynecol 2020; 223 (01) 123.e1-123.e14
    Google Scholar
  • 61 Davidson C, Denning S, Thorp K. et al. Examining the effect of quality improvement initiatives on decreasing racial disparities in maternal morbidity. BMJ Qual Saf 2022; 31 (09) 670-678
    Google Scholar
  • 62 Black Mamas Matter Alliance, Policy Working Group. Advancing holistic maternal care for Black women through policy. Atlanta, GA. December 2018.
    Google Scholar
  • 63 Matthews K, Morgan I, Davis K, Estriplet T, Perez S, Crear-Perry JA. Pathways to equitable and antiracist maternal mental health care: insights from black women stakeholders. Health Aff (Millwood) 2021; 40 (10) 1597-1604
    Google Scholar
  • 64 Howell EA, Brown H, Brumley J. et al. Reduction of peripartum racial and ethnic disparities: a conceptual framework and maternal safety consensus bundle. J Obstet Gynecol Neonatal Nurs 2018; 47 (03) 275-289
    Google Scholar
  • 65 Baumeister L, Marchi K, Pearl M, Williams R, Braveman P. The validity of information on “race” and “Hispanic ethnicity” in California birth certificate data. Health Serv Res 2000; 35 (04) 869-883
    Google Scholar