Severe Maternal Morbidity (SMM) includes potentially life-threatening conditions or complications resulting from the process of labor and delivery. Such outcomes can be considered near-misses for maternal mortality and can result in significant short or long-term consequences to a woman's health1-3. There is currently no consensus as to which specific conditions and complications constitute SMM. Therefore, the process used to identify SMM differs depending on the source of information available and purpose of identification.



For population-based identification and monitoring at state, regional, and national levels, SMM is typically identified using a pre-defined list of International Classification of Disease (ICD) diagnosis and procedure codes that can be found in administrative hospital discharge data. The original list of 25 SMM indicators developed by the U.S. Centers for Disease Control and Prevention (CDC) was based on the 9th Revision of ICD (ICD-9) 3 and was subsequently updated given transition to the 10th Revision of ICD (ICD-10) in the United States in October 20154. The CDC currently lists 21 indicators and corresponding ICD-9 and ICD-10 codes that can be used for population-based identification of SMM6. The use of these indicators for SMM identification has been validated against a clinical gold standard and found to perform reasonably well as a measure in administrative population-based data5. A population-level measure is needed to monitor the overall burden of SMM in a population and to track the impact of large maternal health initiatives and programs.



The CDC, the American College of Obstetricians and Gynecologists (ACOG), and the Society for Maternal-Fetal Medicine (SMFM) recommend that birthing facilities routinely identify and review SMM cases1,7,8. Use of ICD codes to identify SMM cases in facilities is more difficult to operationalize and may lead to missed cases1. Therefore, the definition proposed for facility-based identification of SMM cases includes only two criteria, admission to an intensive care unit (ICU) and/or transfusion of 4 or more units of blood7. Using these criteria alone was found to identify a significant number of SMM cases and to offer learning opportunities for clinicians.

The review of SMM cases should include a timeline for and characterization of events that led to morbidity, as well as a determination of whether the case was preventable with one or more changes in the patient, provider, health facility, or health system factors. By identifying preventable or potentially preventable SMM cases and associated factors, facilities learn what worked and did not work in the process of care. As a result, they can recommend and implement specific practice changes or quality improvement initiatives to prevent future SMM and other adverse maternal outcomes from occurring.


To date, only Illinois has a formal statewide SMM surveillance and review process in place9. A systematic, ongoing process for case identification, clinical review, and analysis of SMM at the hospital and state-level is needed to identify strategies to improve service delivery and quality of care for pregnant and postpartum women in Maryland.

In July 2020, the MDMOM Program launched a HOSPTIAL-BASED PILOT PROGRAM IN SIX BIRTHING HOSPITALS (Ann Arundel Medical Center, Howard County General Hospital, Johns Hopkins Hospital, MedStar St. Mary's Hospital, Mercy Medical Center and Sinai Hospital of Baltimore) to test processes for SMM surveillance and review in Maryland. This pilot is the first phase of a larger initiative to establish a voluntary statewide SMM surveillance and review program in Maryland, as outlined below.

July 2020

Pilot Program Launch & Data Abstractor Training

August 2020

Pilot Program Data Abstraction Start

June 2021

Pilot Program End

July-August 2021

Evaluation Pilot Program

September 2021

Program Scale-Up

The SMM SURVEILLANCE CASE DEFINITION IN MARYLAND is adapted from the proposed CDC/AGOG/SMFM definition for facility-based surveillance7. It includes all women admitted to an ICU or critical care unit, +/- women with 4 or more units of red blood cells transfused, +/- women affected by emerging public health threats requiring hospital admission and treatment (e.g., COVID-19). MDMOM developed standard case identification, abstraction, and review protocols to be used during the pilot phase.

1. LEAD DATA ABSTRACTORS at each hospital identify SMM cases, abstract, and enter relevant case information, into a surveillance database developed by MDMOM health informatics specialists and housed on the MDMOM program website. The database is a web-based, password-protected data entry platform with real-time logic, skip patterns and input validation features.

2. Upon ABSTRACTION OF DATA from several cases, multidisciplinary hospital-based review committees meet to review cases and assess their preventability. Final changes in the MDMOM SMM surveillance database are made following review meetings.

3. Comprehensive ANNUAL HOSPITAL-BASED SMM SURVEILLANCE REPORTS will present all available state data in aggregate. Reports will be made available on our website as they become available.


References & Key Resources

  • American College of Obstetrecians and Gynecologists and the Society for Maternal-Fetal Medicine, Kilpatrick SK, Ecker IL. Severe matenral morbidity: screening and review. Am. J. Obstet Gynecol. 2016;215:817-22
  • Kilpatrick SJ, Berg C, Bernstein P, Bingham D, Delgado A, Callaghan WM, Harris K, Lanni S, Mahoney J, Main E, Nacht A, Schellpfeffer M, Westover T, Harper M. Standardized severe maternal morbidity review: rationale and process. Obstst Gynecol. 2014 Aug124(2Pt1):361-366
  • Callaghan Wm, Creanga AA, Kuklina EV. Severe maternal morbidity among delivery and postpartum hospitalizations in the United States. Obstet Gynecol. 2012 Nov: 120(5):1029-36.
  • Centers for Disease Control and Prevention, How Does CDC Identify Severe Maternal Morbidity? Available at Link
  • Main EK, Abrea A, McNulty J, Gilbert W, McNally C, Poeltler D, et al. Measuring severe maternal morbidity: validation of potential measures. Am J Obstet Gynecol 2016:214:643.e1-10.
  • Centers for Disease Control and Prevention, Maternal and Infant Health Data; 2019 Available from Link
  • Callaghan WM, Grobman WA, Kilpratick SJ. Main EK, D'Alton M. Facility based identification of women with severe maternal morbidity: It is time to start. Obstst Gynecol, 2014 May; 123(5):978-981
  • Kilpatrick SJ, Berg C, Bernstein P, Bingham D, Delgado A, Callaghan WM, Harris K, Lanni SD, Mahoney J, Main E, Nacht A, Scheilpfeffer M, Westover T, Harper M. Stnadardized severe maternal morbidity review rationale and process. Obstet Gynecol. 2014 Aug 124 (2 Pt 1):361-366
  • Illinois Maternal Morbidity and Mortality Report. Illinois Department of Public Health. 2018. Available from Link
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