Background
Methods
Population
Statistical analysis
Results
Frequency of hypertensive disease
Maternal characteristics
Variable | Normotensive n = 121,760 | Mild PIH n = 10,460 | Severe PIH n = 1,770 | HELLP n = 202 | Eclampsia n = 32 | Chronic HTN n = 767 | Chronic HTN +PIH n = 475 |
---|---|---|---|---|---|---|---|
Mean age in years (SD) | 27.8 (5.3) | 27.5 (5.4)* | 26.9 (5.7)* | 28.9 (5.5)* | 25.6 (6.8)* | 31.1 (5.0)* | 30.5 (5.1)* |
Married (%) | 84,739 (69.6) | 7,530 (72.0) | 1,124 (63.5)* | 145 (71.8) | 18 (56.3) | 638 (83.2)* | 367 (77.3)* |
Nulliparous (%) | 51,057 (41.9) | 6,760 (64.6)* | 1,328 (75.0)* | 158 (78.2)* | 20 (62.5)* | 324 (42.2)* | 259 (54.5)* |
Mean prepregnancy weight in kg (SD) | 64.4 (13.8) | 70.6 (16.7)* | 67.6 (15.6)* | 66.8 (16.0)* | 68.2 (16.9) | 82.0 (20.9)* | 81.3 (20.9)* |
Mean weight gain in kg (SD) | 14.4 (6.0) | 16.2 (6.9)* | 16.5 (6.9)* | 14.8 (7.0) | 16.2 (6.2) | 12.2 (6.7)* | 13.2 (7.3)* |
Smokes any cigarettes (%) | 35,846 (30.7) | 2,157 (21.5)* | 376 (22.7)* | 31 (16.0)* | 6 (21.4) | 150 (20.4)* | 59 (13.0)* |
Anemia (%) | 3,441 (2.8) | 242 (2.3)* | 78 (4.3)* | 15 (7.4)* | 0 (0) | 31 (4.1) | 20 (4.2) |
Gestational Diabetes (%) | 2,749 (2.3) | 485 (4.6)* | 84 (4.8)* | 3 (1.5) | 2 (6.3) | 70 (9.1)* | 34 (7.2)* |
Preexisting Diabetes (%) | 331 (0.3) | 85 (0.8)* | 29 (1.6)* | 4 (2.0)* | 0 (0) | 19 (2.5)* | 9 (1.9)* |
Anti-hypertensive medication (%) | 0 (0) | 107 (1.0) | 97 (5.5) | 23 (11.4) | 5 (15.6) | 146 (19.0) | 122 (25.7) |
Twins (%) | 1,231 (1.0) | 244 (2.3)* | 60 (3.4)* | 13 (6.4)* | 0 (0) | 7 (0.9) | 13 (2.7)* |
Small for gestational age
Total No. | SGA | Relative Risk | 95% CI |
P value | ||
---|---|---|---|---|---|---|
No. | % | |||||
Normotensive women | 122,394 | 12,032 | 9.8 | 1.0 | - | - |
All hypertensive women | 13,940 | 2,131 | 15.3 | 1.6 | 1.5,1.6 | <0.001 |
Mild PIH | 10,639 | 1,384 | 13.0 | 1.3 | 1.3,1.4 | <0.001 |
Severe PIH | 1,814 | 453 | 25.0 | 2.5 | 2.3,2.8 | <0.001 |
HELLP | 212 | 79 | 37.3 | 3.8 | 3.2,4.5 | <0.001 |
Eclampsia | 32 | 11 | 34.4 | 3.5 | 2.2,5.7 | <0.001 |
Chronic Hypertension | 766 | 102 | 13.3 | 1.4 | 1.1,1.6 | 0.002 |
Chronic hypertension and PIH | 477 | 102 | 21.4 | 2.2 | 1.8,2.6 | <0.001 |
Stillbirth
Total No. | Stillbirths | Relative Risk | 95% CI |
P value | ||
---|---|---|---|---|---|---|
No. | % | |||||
Normotensive women | 122,855 | 461 | 0.4 | 1.0 | - | - |
All hypertensive women | 14,013 | 73 | 0.52 | 1.4 | 1.1,1.8 | 0.01 |
Mild PIH | 10,683 | 44 | 0.4 | 1.1 | 0.8,1.5 | 0.55 |
Severe PIH | 1,826 | 12 | 0.7 | 1.8 | 1.0,3.1 | 0.50 |
HELLP | 214 | 2 | 0.9 | 2.5 | 0.6,9.9 | 0.19 |
Eclampsia | 32 | 0 | 0.0 | - | 0.0,41.0 | 1.00 |
Chronic Hypertension | 773 | 7 | 0.9 | 2.4 | 1.2,5.1 | 0.03 |
Chronic hypertension and PIH | 485 | 8 | 1.7 | 4.4 | 2.2,8.8 | <0.001 |
Crude | Adjusted | |||||
---|---|---|---|---|---|---|
Odds ratio | 95% CI |
P value | Odds ratio | 95% CI |
P value | |
Small for gestational age*
| ||||||
Normotensive women | 1.0 | - | - | 1.0 | - | - |
Hypertensive women (any type) | 1.6 | 1.5,1.6 | <0.001 | 1.8 | 1.7,1.9 | <0.001 |
Gestational hypertension without proteinuria | 1.3 | 1.3,1.4 | <0.001 | 1.5 | 1.4,1.6 | <0.001 |
Gestational hypertension withproteinuria | 2.7 | 2.5,2.9 | <0.001 | 3.3 | 3.0,3.9 | <0.001 |
Pre-existing hypertension | 1.7 | 1.5,1.9 | <0.001 | 2.5 | 2.1,2.9 | <0.001 |
Stillbirth**
| ||||||
Normotensive women | 1.0 | - | - | 1.0 | - | - |
Hypertensive women (any type) | 1.4 | 1.1,1.8 | 0.01 | 1.4 | 1.1,1.8 | 0.02 |
Gestational hypertension without proteinuria | 1.1 | 0.8,1.5 | 0.55 | 1.1 | 0.8,1.5 | 0.60 |
Gestational hypertension with proteinuria | 1.8 | 1.0,3.1 | 0.03 | 1.6 | 0.9,2.9 | 0.08 |
Pre-existing hypertension | 3.2 | 1.9,5.3 | <0.001 | 3.2 | 1.9,5.4 | <0.001 |
Adjusted | |||
---|---|---|---|
Odds ratio | 95% CI |
P value | |
Small for gestational age
| |||
Normotensive women | 1.0 | - | - |
Gestational hypertension without proteinuria | 1.5 | 1.4,1.6 | <0.001 |
Gestational hypertension with proteinuria | 3.7 | 3.3,4.1 | <0.001 |
Pre-existing hypertension | 2.5 | 2.1,3.0 | <0.001 |
Twins | 4.7 | 4.3,5.2 | <0.001 |
Gestational hypertension without proteinuria × twins | 0.7 | 0.6,0.9 | 0.01 |
Gestational hypertension with proteinuria × twins | 0.3 | 0.2,0.4 | <0.001 |
Pre-existing hypertension × twins | 0.7 | 0.3,1.4 | 0.29 |
Smoking | 2.9 | 2.8,3.0 | <0.001 |
Gestational hypertension without proteinuria × smoking | 1.0 | 0.9,1.2 | 0.96 |
Gestational hypertension with proteinuria × smoking | 0.9 | 0.7,1.1 | 0.28 |
Pre-existing hypertension × smoking | 0.6 | 0.4,0.8 | 0.002 |
Stillbirth
| |||
Normotensive women | 1.0 | - | - |
Gestational hypertension without proteinuria | 0.8 | 0.5,1.2 | 0.24 |
Gestational hypertension with proteinuria | 1.4 | 0.6,2.9 | 0.42 |
Pre-existing hypertension | 3.5 | 2.0,6.2 | <0.001 |
Smoking | 1.4 | 1.2,1.7 | <0.001 |
Gestational hypertension without proteinuria × smoking | 2.5 | 1.3,4.7 | 0.006 |
Gestational hypertension with proteinuria × smoking | 1.8 | 0.4,5.3 | 0.33 |
Pre-existing hypertension × smoking | 0.6 | 0.1,2.5 | 0.43 |