On this page: About the National Data | Methodology | History | References
About the National Data
Data
Baseline: 71.5 per 10,000 delivery hospitalizations had severe maternal complications in 2017
Target: 64.4 per 10,000
Methodology
Methodology notes
This measure originally followed the CDC-developed definition of severe maternal morbidity identified from hospital discharge procedure and diagnosis codes that indicate a potentially life-threatening condition or maternal complication (Callaghan et al, 2012). Specific ICD-9-CM diagnosis and procedure codes had been reduced to 21 indicators (18 if 3 are collapsed) in preparation for the transition to ICD-10-CM and described in detail by the National Center for Chronic Disease Prevention and Health Promotion, CDC. The transition from ICD-9-CM to ICD-10-CM/PCS coding of hospital discharge information required a re-alignment of the SMM algorithm. CDC, HRSA and AHRQ collaborated to produce the revised definition used for Healthy People 2030.
With the exception of hospitalizations with in-hospital mortality, transfer, or severe complications identified by procedure codes (e.g., hysterectomy, blood transfusion, ventilation), cases of severe maternal morbidity identified by diagnostic codes were reclassified as hospitalizations without severe maternal morbidity if they had an implausibly short length of stay (≤ 3 days for vaginal,<4 days for primary cesarean, and < 5 days for repeat cesarean deliveries). Delivery hospitalizations were identified by diagnosis codes for an outcome of delivery, diagnosis-related group delivery codes, and procedure codes for selected delivery-related procedures (Kuklina et al, 2008).
Although blood transfusions are significant maternal health events and can be an indicator of SMM, they may not always reflect SMM in the absence of other indicators. As a result of this and changes in data reporting, SMM estimates provided here do not include those who only received blood transfusions.
The HCUP-NIS data represent 97% of inpatient discharges from community hospitals and do not include all states.
History
In 2023, the baseline was revised from 68.7 per 10,000 labor and delivery hospitalizations to 71.5 per 10,000 labor and delivery hospitalizations. The target was revised from 61.8 per 10,000 to 64.4 per 10,000 due to changes in methodology.
References
Additional resources about the objective
- American College of Obstetricians and Gynecologists and the Society for Maternal–Fetal Medicine, Kilpatrick SK, Ecker JL. Severe maternal morbidity: screening and review. Am J Obstet Gynecol. 2016 Sep;215(3):B17-22. doi: 10.1016/j.ajog.2016.07.050. Epub 2016 Aug 22. PMID: 27560600.
- Martin JA, Hamilton BE, Osterman MJK, Driscoll AK, Matthews TJ. Births: Final data for 2015. National vital statistics report; vol 66, no 1. Hyattsville, MD: National Center for Health Statistics. 2017.
- Hinkle SN, Sharma AJ, Kim SY, Park S, Dalenius K, Brindley PL, Grummer-Strawn LM. Prepregnancy obesity trends among low-income women, United States, 1999-2008. Matern Child Health J. 2012 Oct;16(7):1339-48. doi: 10.1007/s10995-011-0898-2. PMID: 22009444.
- Fisher SC, Kim SY, Sharma AJ, Rochat R, Morrow B. Is obesity still increasing among pregnant women? Prepregnancy obesity trends in 20 states, 2003-2009. Prev Med. 2013 Jun;56(6):372-8. doi: 10.1016/j.ypmed.2013.02.015. Epub 2013 Feb 27. PMID: 23454595; PMCID: PMC4424789.
- Campbell KH, Savitz D, Werner EF, Pettker CM, Goffman D, Chazotte C, Lipkind HS. Maternal morbidity and risk of death at delivery hospitalization. Obstet Gynecol. 2013 Sep;122(3):627-33. doi: 10.1097/AOG.0b013e3182a06f4e. PMID: 23921870.
- Small MJ, James AH, Kershaw T, Thames B, Gunatilake R, Brown H. Near-miss maternal mortality: cardiac dysfunction as the principal cause of obstetric intensive care unit admissions. Obstet Gynecol. 2012 Feb;119(2 Pt 1):250-5. doi: 10.1097/AOG.0b013e31824265c7. PMID: 22270275.
- Barber EL, Lundsberg LS, Belanger K, Pettker CM, Funai EF, Illuzzi JL. Indications contributing to the increasing cesarean delivery rate. Obstet Gynecol. 2011 Jul;118(1):29-38. doi: 10.1097/AOG.0b013e31821e5f65. PMID: 21646928; PMCID: PMC3751192.
- 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. doi: 10.1097/aog.0b013e31826d60c5. PMID: 23090519.