APPENDIX A: List of International Classification of Diseases, 9th Edition, Clinical Modification Codes Used to Identify Selected Clinical and Behavioral Conditions.

Condition International Classification of Diseases, 9th Edition, Diagnosis Codea
Exposure
 Cervical cancer 180, 795.06, 233.1
Comorbidities
 Obesity 278.00, 278.01, 278.03, 649.1x, V85.3x, V85.4x, V85.54, 793.91
 Pre-pregnancy hypertension 401x, 402x, 403x, 404x, 405x, 642.0x, 642.1x, 642.2x, 642.7x
 Pre-pregnancy diabetes 249x, 250x, 648.0x
 Coronary heart disease 410x, 411x, 412x, 413x, 414x, 429.2
 Chronic renal disease 581x, 582x, 583x, 585x, 587x, 646.2x
 Anemia 280x, 281x, 282x, 283x, 284x, 285x, 648.2x
 Disorders of lipid metabolism (e.g., hyperlipidemia) 272x
 Hypothyroidism 243x, 244x
 Disorders of the adrenal glands 255x
 Cesarean sectionb 74x
 Gestational diabetes 648.8x
 Gestational hypertension 642.3x
 Pre-eclampsia 642.4x, 642.5x
 Eclampsia 642.6x
 Acute renal failure 584x, 669.3x
 HIV 042x, 043x, 044x, 079.53, 279.10, 279.19, 795.71, 795.8, V08
 STD 090.x, 091.x, 092.x, 093.x, 094.x, 095.x, 096.x, 097.x, 098.x, 099.x, 795.05, 795.15, 795.19, 796.75, 796.69
Perinatal history
 Previous Cesarean section 654.2x
Behavioral history
 Tobacco use 305.1, 649.0x, 989.84
 Alcohol use 291x, 303x, 305.0x, 425.5, 760.71, V11.3
 Drug use 292.0x, 292.1x, 292.2x, 292.8x, 304x, 305.2x, 305.3x, 305.4x, 305.5x, 305.6x, 305.7x, 305.9x, 648.3x, 655.5x, 760.72, 779.5, 760.75, 965.00, 965.02, E935.1, E850.1
Maternal outcomes
 Anemia 280x, 281x, 282x, 283x, 284x, 285x, 648.2x
Fetal outcomes
 Preterm labor 644.2x
 Poor fetal growth 656.5x

aThe code suffix “x” represents all possible codes that follow the stated code prefix. bprocedure codes, not diagnostic codes were used to define Cesarean section