Importance: More pregnant women have complex medical histories known to increase maternal morbidity and mortality.  While the association between individual co-morbidities and complications has been studied, the joint effect of multiple pre-gestational diagnoses is unclear. 

Objective: To determine the most common combinations of pre-gestational diagnoses and their potential synergistic effects on common pregnancy-related complications.

Design: This was a cross-sectional study of data from the 2016 Healthcare Cost and Utilization Project’s National Inpatient Sample database.  A chi-squared analyses of combinations of pre-gestational diagnoses was performed to assess the relative risk of pregnancy-related complications.

Setting: Largest all payer hospital inpatient care database in the United States. 

Participants: Inclusion criteria were: Diagnosis Related Groups assumed to be associated with delivery, and three or less ICD 10 codes with a prevalence greater than or equal to 0.5% or clinically important risk factors in Bateman’s co-morbidity index.  Exclusion criteria included: Diagnosis Related Groups assumed not to be associated with delivery, uncommon diagnoses not defined a-priori, missing ICD 10 codes, or four or more ICD 10 codes.  

Main outcome and measure: Most common combination of diagnoses and the relative risk of complications.

Enter diagnosis #1
arrow&v
Enter diagnosis #2
arrow&v
Diagnosis 1
Diagnosis 2
Compared to
None
GDM
Laceration
Meconium
Non-Vtx
NRFHT
Pre-E
IUGR
LGA
Hemorrhage
Anemia
Obesity
Anemia
1.02
3.31
0.74
1.37
1.02
1.36
2.42
0.87
2.58
1.03
Anemia
Tobacco use
No diagnosis
1.1
0.13
0.96
1.89
0.69
1.15
0.69
0.98
3.1
6.55
Anemia
Tobacco use
Anemia
1.18
1.04
0.8
1.54
1.19
1.16
0.86
2.41
1.19
0.92
Anemia
Tobacco use
Tobacco use
0.95
0.74
0.86
1.08
1.19
1.07
0.75
1.1
2.23
9.06
Fibroid
Advanced maternal age
No diagnosis
0.76
0.48
0.83
0.39
3
2.48
1.16
0.78
4.66
0.52
Fibroid
Advanced maternal age
Fibroid
1.04
1.76
0.78
0.4
1.1
1.4
0.99
1.98
0.85
NONE in fibroid alone
Fibroid
Advanced maternal age
Advanced maternal age
0.98
1.29
0.58
0.3
3.35
2.59
1.64
2.61
1.22
1
Obesity
Hypertension
No diagnosis
1.02
0.66
0.92
0.92
0.57
1.96
1.38
0.61
6.12
1.63
Obesity
Hypertension
Obesity
1.12
1.71
0.85
0.44
0.7
1.57
0.63
2.15
0.79
2.46
Obesity
Hypertension
Hypertension
0.86
1.84
0.85
1.44
1.01
2.13
0.85
1.93
2.89
2.89
Obesity
Advanced maternal age
No diagnosis
0.87
0.78
1.03
1.36
0.86
0.77
3.13
No cases
10.16
0.45
Obesity
Advanced maternal age
Obesity
0.95
2.03
0.96
0.65
1.05
0.61
1.43
No cases
1.31
0.68
Obesity
Advanced maternal age
Advanced maternal age
1.12
2.12
0.72
1.05
0.96
0.8
4.41
No cases
2.66
0.87
Previous cesarean
Anemia
No diagnosis
1.8
0.37
0.1
0.77
0.34
0.29
0.91
0.36
2.34
20.38
Previous cesarean
Anemia
Anemia
1.92
2.93
0.08
0.63
0.59
0.29
1.13
0.89
0.89
2.87
Previous cesarean
Anemia
Previous cesarean
0.78
0.81
0.6
0.78
0.7
0.99
0.81
0.97
0.88
27.67
Previous cesarean
Hypertension
No diagnosis
2.1
1.11
0.05
1.44
0.43
0.43
1.98
0.84
1.44
0.96
Previous cesarean
Hypertension
Hypertension
1.76
3.09
0.05
2.26
0.76
0.47
1.22
2.64
0.68
1.7
Previous cesarean
Hypertension
Previous cesarean
0.92
2.4
0.3
1.45
0.89
1.47
1.76
2.26
0.54
1.3
Previous cesarean
Advanced maternal age
No diagnosis
2.16
0.85
0.15
1.4
0.61
0.38
1.1
0.25
2.95
0.68
Previous cesarean
Advanced maternal age
Previous cesarean
0.94
0.85
0.15
1.4
0.61
0.38
1.1
0.25
2.95
0.68
Previous cesarean
Advanced maternal age
Advanced maternal age
2.79
0.85
0.15
1.4
0.61
0.38
1.1
0.25
2.95
0.68
Previous cesarean
Obesity
No diagnosis
2.04
1.02
0.09
1.19
0.41
0.31
2.79
0.29
5.54
1
Previous cesarean
Obesity
Previous cesarean
0.89
2.22
0.53
1.19
0.84
1.04
2.48
0.78
2.08
1.36
Previous cesarean
Obesity
Obesity
2.23
2.65
0.08
0.57
0.5
0.24
1.28
1.02
0.71
1.51
Previous cesarean
Tobacco use
No diagnosis
2.3
0.45
0.12
0.99
0.53
0.35
1.09
0.99
1.15
0.93
Previous cesarean
Tobacco use
Previous cesarean
1
0.97
0.74
0.99
1.08
1.2
0.97
2.65
0.43
1.26
Previous cesarean
Tobacco use
Tobacco use
1.99
2.51
0.11
0.56
0.91
0.33
1.18
1.11
0.83
1.29
Tobacco use
Advanced maternal age
No diagnosis
0.84
0.46
1.23
2.58
0.84
1.15
0.79
1.24
2.29
0.57
Tobacco use
Advanced maternal age
Tobacco use
0.73
2.59
1.1
1.46
1.45
1.07
0.86
1.39
1.64
0.79
Tobacco use
Advanced maternal age
Advanced maternal age
1.08
1.25
0.86
2
0.94
1.2
1.11
4.17
0.6
1.1
Tobacco use
Obesity
No diagnosis
0.94
0.37
1.07
1.71
0.95
1.4
1.57
0.66
5.12
0.95
Tobacco use
Obesity
Tobacco use
0.81
2.08
0.96
0.97
1.63
1.31
1.7
0.75
3.68
1.31
Tobacco use
Obesity
Obesity
1.03
0.97
0.99
0.82
1.16
1.12
0.72
2.34
0.66
1.43
Tobacco use
Substance use
No diagnosis
1.35
0.07
0.84
2.73
0.56
1.33
0.4
2.47
0.64
0.86
Tobacco use
Substance use
Tobacco use
1.16801272
0.41560241
0.753781523
1.552800212
0.960503347
1.235844096
0.437476221
2.770682731
0.461780455
1.187435456
Tobacco use
Substance use
Substance use
1.167692571
0.782168675
0.820323244
1.582960413
0.806999426
0.878522787
0.383416017
1.998875502
0.434538153
1.303614458
Hypertension
Previous cesarean
Hypertension
1.76
3.09
0.05
2.26
0.76
0.47
1.22
2.64
0.68
1.7
Advanced maternal age
Previous cesarean
No diagnosis
2.16
0.85
0.15
1.4
0.61
0.38
1.1
0.25
2.95
0.68
Advanced maternal age
Previous cesarean
Previous cesarean
0.94
0.85
0.15
1.4
0.61
0.38
1.1
0.25
2.95
0.68
Advanced maternal age
Previous cesarean
Advanced maternal age
2.79
0.85
0.15
1.4
0.61
0.38
1.1
0.25
2.95
0.68
Obesity
Previous cesarean
No diagnosis
2.04
1.02
0.09
1.19
0.41
0.31
2.79
0.29
5.54
1
Obesity
Previous cesarean
Previous cesarean
0.89
2.22
0.53
1.19
0.84
1.04
2.48
0.78
2.08
1.36
Obesity
Previous cesarean
Obesity
2.23
2.65
0.08
0.57
0.5
0.24
1.28
1.02
0.71
1.51
Tobacco use
Previous cesarean
No diagnosis
2.3
0.45
0.12
0.99
0.53
0.35
1.09
0.99
1.15
0.93
Tobacco use
Previous cesarean
Previous cesarean
1
0.97
0.74
0.99
1.08
1.2
0.97
2.65
0.43
1.26
Tobacco use
Previous cesarean
Tobacco use
1.99
2.51
0.11
0.56
0.91
0.33
1.18
1.11
0.83
1.29
Advanced maternal age
Tobacco use
No diagnosis
0.84
0.46
1.23
2.58
0.84
1.15
0.79
1.24
2.29
0.57
Advanced maternal age
Tobacco use
Tobacco use
0.73
2.59
1.1
1.46
1.45
1.07
0.86
1.39
1.64
0.79
Advanced maternal age
Tobacco use
Advanced maternal age
1.08
1.25
0.86
2
0.94
1.2
1.11
4.17
0.6
1.1
Obesity
Tobacco use
No diagnosis
0.94
0.37
1.07
1.71
0.95
1.4
1.57
0.66
5.12
0.95
Obesity
Tobacco use
Tobacco use
0.81
2.08
0.96
0.97
1.63
1.31
1.7
0.75
3.68
1.31
Obesity
Tobacco use
Obesity
1.03
0.97
0.99
0.82
1.16
1.12
0.72
2.34
0.66
1.43
Substance use
Tobacco use
No diagnosis
1.35
0.07
0.84
2.73
0.56
1.33
0.4
2.47
0.64
0.86
Substance use
Tobacco use
Tobacco use
1.16801272
0.41560241
0.753781523
1.552800212
0.960503347
1.235844096
0.437476221
2.770682731
0.461780455
1.187435456
Substance use
Tobacco use
Substance use
1.167692571
0.782168675
0.820323244
1.582960413
0.806999426
0.878522787
0.383416017
1.998875502
0.434538153
1.303614458
No diagnosis
Pregestational DM
N/A
0.95
0.21
0.93
0.68
0.99
1.45
2.71
No cases
20.33
0.9
No diagnosis
Hypertension
N/A
1.19
0.36
1.08
0.64
0.57
0.92
1.62
0.32
2.12
0.57
No diagnosis
Previous cesarean
N/A
2.29
0.46
0.17
1
0.49
0.29
1.12
0.37
2.67
0.74
No diagnosis
Psychiatric diagnosis
N/A
1.05
0.13
1.35
1.6
0.38
0.75
0.8
0.38
1.88
0.5
No diagnosis
Fibroid
N/A
0.73
0.27
1.06
0.98
2.72
1.78
1.18
0.39
5.5
No cases
No diagnosis
Advanced maternal age
N/A
0.78
0.37
1.43
1.29
0.9
0.96
0.71
0.3
3.82
0.52
No diagnosis
Obesity
N/A
0.91
0.39
1.08
2.08
0.82
1.25
2.19
0.28
7.75
0.66
No diagnosis
Substance use
N/A
1.16
0.09
1.02
1.73
0.69
1.51
1.05
1.23
1.48
0.66
No diagnosis
Tobacco use
N/A
1.16
0.18
1.11
1.76
0.58
1.08
0.92
0.89
1.39
0.72
No diagnosis
Asthma
N/A
1
0.25
1.19
0.8
0.43
1.5
2.01
0.27
1.61
0.54
No diagnosis
Anemia
N/A
0.94
0.13
1.19
1.23
0.58
0.99
0.8
0.4
2.62
7.1
Advanced maternal age
Hypertension
No diagnosis
0.97
6.94
0.75
0.81
1.64
1.22
1.31
2.66
0.45
1.94
Advanced maternal age
Hypertension
Hypertension
0.84
2.79
0.93
1.57
1.77
1.09
0.62
3.14
0.47
1.77
Advanced maternal age
Hypertension
Advanced maternal age
1.29
2.71
0.7
0.78
1.12
1.04
1.41
3.36
0.26
1.92
Anemia
Sickle Cell
No diagnosis
1.14
0.09
1.16
1.22
0.45
1.55
0.46
0.51
1.83
1.22
Anemia
Sickle Cell
Anemia
1.22
0.74
0.97
1
0.77
1.56
0.57
1.26
0.7
0.17
Anemia
Advanced maternal age
No diagnosis
0.86
0.39
1.13
1.36
1
1.07
0.89
0.4
3.06
6.24
Anemia
Advanced maternal age
Anemia
0.92
3.08
0.95
1.11
1.72
1.08
1.11
0.98
1.17
0.88
Anemia
Advanced maternal age
Advanced maternal age
1.1
1.06
0.79
1.06
1.11
1.11
1.26
1.33
0.8
11.99
Anemia
Obesity
No diagnosis
0.95
0.42
0.89
1.68
0.59
1.35
1.95
0.35
6.74
7.3
Anemia
Obesity
Obesity
1.04
1.09
0.83
0.81
0.72
1.08
0.89
1.23
0.87
11
No diagnosis
No diagnosis
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Pregestational DM
No diagnosis
N/A
0.95
0.21
0.93
0.68
0.99
1.45
2.71
No cases
20.33
0.9
Hypertension
No diagnosis
N/A
1.19
0.36
1.08
0.64
0.57
0.92
1.62
0.32
2.12
0.57
Previous cesarean
No diagnosis
N/A
2.29
0.46
0.17
1
0.49
0.29
1.12
0.37
2.67
0.74
Psychiatric diagnosis
No diagnosis
N/A
1.05
0.13
1.35
1.6
0.38
0.75
0.8
0.38
1.88
0.5
Fibroid
No diagnosis
N/A
0.73
0.27
1.06
0.98
2.72
1.78
1.18
0.39
5.5
No cases
Advanced maternal age
No diagnosis
N/A
0.78
0.37
1.43
1.29
0.9
0.96
0.71
0.3
3.82
0.52
Obesity
No diagnosis
N/A
0.91
0.39
1.08
2.08
0.82
1.25
2.19
0.28
7.75
0.66
Substance use
No diagnosis
N/A
1.16
0.09
1.02
1.73
0.69
1.51
1.05
1.23
1.48
0.66
Tobacco use
No diagnosis
N/A
1.16
0.18
1.11
1.76
0.58
1.08
0.92
0.89
1.39
0.72
Asthma
No diagnosis
N/A
1
0.25
1.19
0.8
0.43
1.5
2.01
0.27
1.61
0.54
Anemia
No diagnosis
N/A
0.94
0.13
1.19
1.23
0.58
0.99
0.8
0.4
2.62
7.1
Hypertension
Advanced maternal age
No diagnosis
0.97
6.54
0.75
0.81
1.64
1.22
1.31
2.66
0.45
1.94
Hypertension
Advanced maternal age
Hypertension
0.84
2.79
0.93
1.57
1.77
1.09
0.62
3.14
0.47
1.77
Hypertension
Advanced maternal age
Advanced maternal age
1.29
2.71
0.7
0.78
1.12
1.04
1.41
3.36
0.26
1.92
Sickle Cell
Anemia
No diagnosis
1.14
0.09
1.16
1.22
0.45
1.55
0.46
0.51
1.83
1.22
Sickle Cell
Anemia
Anemia
1.22
0.74
0.97
1
0.77
1.56
0.57
1.26
0.7
0.17
Advanced maternal age
Anemia
No diagnosis
0.86
0.39
1.13
1.36
1
1.07
0.89
0.4
3.06
6.24
Advanced maternal age
Anemia
Anemia
0.92
3.08
0.95
1.11
1.72
1.08
1.11
0.98
1.17
0.88
Advanced maternal age
Anemia
Advanced maternal age
1.1
1.06
0.79
1.06
1.11
1.11
1.26
1.33
0.8
11.99
Obesity
Anemia
No diagnosis
0.95
0.42
0.89
1.68
0.59
1.35
1.95
0.35
6.74
7.3
Obesity
Anemia
Obesity
1.04
1.09
0.83
0.81
0.72
1.08
0.89
1.23
0.87
11
Obesity
Anemia
Anemia
1.02
3.31
0.74
1.37
1.02
1.36
2.42
0.87
2.58
1.03
Tobacco use
Anemia
No diagnosis
1.1
0.13
0.96
1.89
0.69
1.15
0.69
0.98
3.1
6.55
Tobacco use
Anemia
Anemia
1.18
1.04
0.8
1.54
1.19
1.16
0.86
2.41
1.19
0.92
Tobacco use
Anemia
Tobacco use
0.95
0.74
0.86
1.08
1.19
1.07
0.75
1.1
2.23
9.06
Advanced maternal age
Fibroid
No diagnosis
0.76
0.48
0.83
0.39
3
2.48
1.16
0.78
4.66
0.52
Advanced maternal age
Fibroid
Fibroid
1.04
1.76
0.78
0.4
1.1
1.4
0.99
1.98
0.85
NONE in fibroid alone
Advanced maternal age
Fibroid
Advanced maternal age
0.98
1.29
0.58
0.3
3.35
2.59
1.64
2.61
1.22
1
Hypertension
Obesity
No diagnosis
1.02
0.66
0.92
0.92
0.57
1.96
1.38
0.61
6.12
1.63
Hypertension
Obesity
Obesity
1.12
1.71
0.85
0.44
0.7
1.57
0.63
2.15
0.79
2.46
Hypertension
Obesity
Hypertension
0.86
1.84
0.85
1.44
1.01
2.13
0.85
1.93
2.89
2.89
Advanced maternal age
Obesity
No diagnosis
0.87
0.78
1.03
1.36
0.86
0.77
3.13
No cases
10.16
0.45
Advanced maternal age
Obesity
Obesity
0.95
2.03
0.96
0.65
1.05
0.61
1.43
No cases
1.31
0.68
Advanced maternal age
Obesity
Advanced maternal age
1.12
2.12
0.72
1.05
0.96
0.8
4.41
No cases
2.66
0.87
Anemia
Previous cesarean
No diagnosis
1.8
0.37
0.1
0.77
0.34
0.29
0.91
0.36
2.34
20.38
Anemia
Previous cesarean
Anemia
1.92
2.93
0.08
0.63
0.59
0.29
1.13
0.89
0.89
2.87
Anemia
Previous cesarean
Previous cesarean
0.78
0.81
0.6
0.78
0.7
0.99
0.81
0.97
0.88
27.67
Hypertension
Previous cesarean
No diagnosis
2.1
1.11
0.05
1.44
0.43
0.43
1.98
0.84
1.44
0.96
Hypertension
Previous cesarean
Previous cesarean
0.92
2.4
0.3
1.45
0.89
1.47
1.76
2.26
0.54
1.3

GDM: gestational diabetes

Pre-E: Pre-eclampsia

Note: some combinations of diagnoses were not studied together due to low prevalence (for example, there were very few patients with pre-gestational diabetes and no other diagnoses). If the combination was not able to be studied, the table will return blank results.