How Does CDC Identify Severe Maternal Morbidity?

To identify delivery hospitalizations with SMM, CDC uses administrative hospital discharge data and International Classification of Diseases (ICD) diagnosis and procedure codes. The original list of 25 SMM indicators based on the 9th Revision of ICD was published in 2012.2 In October 2015, the United States transitioned to the 10th Revision of ICD to code diagnoses and procedures. CDC, along with our clinical and public health partners, took the opportunity to review this new version of ICD coding to update the indicators, taking into account results from validation studies. The updated list of 21 indicators and corresponding ICD codes used to identify delivery hospitalizations with SMM for both ICD-9 and ICD-10 can be used to track SMM when using administrative hospital discharge data from October 2015 and beyond.

Severe Morbidity Indicators and Corresponding ICD-9-CM/ICD-10-CM/PCS Codes During Delivery Hospitalizations

The table below includes the list of 21 indicators and corresponding ICD codes used to identify delivery hospitalizations with SMM.

Severe Maternal Morbidity Indicators and Corresponding ICD Codes during
Severe Maternal Morbidity Indicator Diagnosis (DX) or Procedure (PR) Code ICD-9 ICD-10
Acute Myocardial Infarction DX 410.xx I21.xx, I22.x
Aneurysm DX 441.xx I71.xx, I79.0
Acute Renal Failure DX 584.5, 584.6, 584.7, 584.8, 584.9, 669.3x N17.x, O90.4
Acute Respiratory Distress Syndrome DX 518.5x, 518.81, 518.82, 518.84, 799.1 J80, J95.1, J95.2, J95.3, J95.82x, J96.0x, J96.2x, J96.9x, R06.03, R09.2
Amniotic Fluid Embolism DX 673.1x O88.112, O88.113, O88.119, O88.12, O88.13
Cardiac Arrest / Ventricular Fibrillation DX 427.41, 427.42, 427.5 I46.x, I49.0x
Conversion of Cardiac Rhythm PR 99.6x 5A12012, 5A2204Z
Disseminated Intravascular Coagulation DX 286.6, 286.9, 641.3x, 666.3x D65, D68.8, D68.9, O45.002, O45.003, O45.009, O45.012, O45.013, O45.019, O45.022, O45.023, O45.029, O45.092, O45.093, O45.099, O46.002, O46.003, O46.009, O46.012, O46.013, O46.019, O46.022, O46.023, O46.029, O46.092, O46.093, O46.099, O67.0, O72.3
Blood Transfusion* PR 99.0x 30230H0, 30230K0, 30230L0, 30230M0, 30230N0, 30230P0, 30230R0, 30230T0, 30230H1, 30230K1, 30230L1, 30230M1, 30230N1, 30230P1, 30230R1, 30230T1, 30233H0, 30233K0, 30233L0, 30233M0, 30233N0, 30233P0, 30233R0, 30233T0, 30233H1, 30233K1, 30233L1, 30233M1, 30233N1, 30233P1, 30233R1, 30233T1, 30240H0, 30240K0, 30240L0, 30240M0, 30240N0, 30240P0, 30240R0, 30240T0, 30240H1, 30240K1, 30240L1, 30240M1, 30240N1, 30240P1, 30240R1, 30240T1, 30243H0, 30243K0, 30243L0, 30243M0, 30243N0, 30243P0, 30243R0, 30243T0, 30243H1, 30243K1, 30243L1, 30243M1, 30243N1, 30243P1, 30243R1, 30243T1
Eclampsia DX 642.6x O15. X
Heart Failure / Arrest During Surgery or Procedure DX 997.1 I97.120, I97.121, I97.130, I97.131, I97.710, I97.711
Puerperal Cerebrovascular Disorders DX 046.3, 348.39, 362.34, 430.xx, 431.xx, 432.xx, 433.xx, 434.xx, 435.xx, 436.xx, 437.xx, 671.5x, 674.0x, 997.02 A81.2, G45.x, G46.x, G93.49, H34.0x, I60.xx, I61.xx, I62.xx, I63.00, I63.01x, I63.1xx, I63.2xx, I63.3xx, I63.4xx, I63.5xx, I63.6, I63.8x, I63.9, I65.xx, I66.xx, I67.xx, I68.xx, O22.50, O22.52, O22.53, I97.810, I97.811, I97.820, I97.821, O87.3
Pulmonary Edema / Acute Heart Failure DX 428.0, 428.1, 428.20, 428.21, 428.23, 428.30, 428.31, 428.33, 428.40, 428.41, 428.43, 428.9, 518.4 I50.1, I50.20, I50.21, I50.23, I50.30, I50.31, I50.33, I50.40, I50.41, I50.43, I50.810, I50.811, I50.813, I50.814, I50.82, I50.83, I50.84, I50.89, I50.9, J81.0
Severe Anesthesia Complications DX 668.0x, 668.1x, 668.2x, 995.4, 995.86 O29.112-O29.119, O29.122-O29.129, O29.192-O29.199, O29.212-O29.219, O29.292-O29.299, O74.0, O74.1, O74.2, O74.3, O89.0x, O89.1, O89.2, T88.2XXA, T88.3XXA
Sepsis DX 038.xx, 449, 785.52, 995.91, 995.92, 998.02, 670.2x (after October 1, 2009) A32.7, A40.x, A41.x, I76, O85, O86.04, R65.20, R65.21, T81.12XA, T81.44XA
Shock DX 669.1x, 785.50, 785.51, 785.59, 995.0, 998.0*, 998.00, 998.01, 998.09
*998.0 is not a valid code but was used prior to 2012
O75.1, R57.x, T78.2XXA, T81.10XA, T81.11XA, T81.19XA, T88.6XXA
Sickle Cell Disease with Crisis DX 282.42, 282.62, 282.64, 282.69, 289.52 D57.00, D57.01, D57.02, D57.211, D57.212, D57.219, D57.411, D57.412, D57.419, D57.811, D57.812, D57.819
Air and Thrombotic Embolism DX 415.0, 415.1x, 673.0x, 673.2x, 673.3x, 673.8x I26.x, O88.012-O88.03, O88.212-O88.23, O88.312-O88.33, O88.812-O88.83, T80.0XXA
Hysterectomy PR 68.39, 68.49, 68.59, 68.69, 68.79, 68.9 (also include 68.3, 68.4, 68.5, 68.6, 68.7; non-specific codes used frequently) 0UT90ZL, 0UT90ZZ, 0UT97ZL, 0UT97ZZ
Temporary Tracheostomy PR 31.1 0B110F4, 0B113F4, 0B114F4
Ventilation PR 96.70, 96.71, 96.72 5A1935Z, 5A1945Z, 5A1955Z

*Excluded, but could be examined separately.

1. Applicable to delivery hospitalizations for patients aged 12 – 55 years inclusive.

2. Use a code under Z3A (Z3A.20-Z3A.42) to document the exact week during the pregnancy.