Multivariate analysis for VTE risk factors during the postpartum period
| Variable . | IRR (95% CI) . | |||
|---|---|---|---|---|
| MF 1 . | MF 2 . | MF 3 . | MF 3 restricted to spontaneous vaginal/assisted deliveries . | |
| Demographic and lifestyle characteristics | ||||
| Maternal age at delivery | ||||
| Age (for every year increase)* | 1.03 (1.00-1.06) | 1.02 (0.99-1.05) | 1.02 (0.99-1.05) | 1.02 (0.98-1.07) |
| BMI (kg/m2) | ||||
| Normal (18.5-24.9) | 1.00 | 1.00 | 1.00 | 1.00 |
| Underweight (<18.5) | 0.70 (0.21-2.27) | 0.69 (0.21-2.23) | 0.74 (0.23-2.39) | 0.84 (0.19-3.56) |
| Overweight (25-29.9) | 1.35 (0.88-2.07) | 1.36 (0.89-2.09) | 1.21 (0.77-1.90) | 0.67 (0.30-1.46) |
| Obese (30-40) | 2.13 (1.36-3.34) | 2.15 (1.37-3.37) | 1.91 (1.18-3.11) | 2.57 (1.37-4.82) |
| Class 3 obese (≥40) | 7.23 (3.89-13.4) | 7.45 (4.00-13.8) | 6.36 (3.19-12.6) | 11.5 (4.96-26.6) |
| Cigarette smoker | 1.43 (1.03-1.99) | 1.44 (1.04-2.00) | 1.38 (0.97-1.96) | 1.16 (0.71-1.89) |
| Preexisting comorbidities | ||||
| Varicose veins | 3.50 (2.09-5.87) | 3.50 (2.09-5.78) | 3.97 (2.36-6.68) | 4.88 (2.61-9.11) |
| Cardiac disease | 2.67 (1.09-6.53) | 2.59 (1.05-6.33) | 2.78 (1.02-7.53) | 2.69 (0.66-10.9) |
| Inflammatory bowel disease | 4.59 (1.69-12.4) | 4.61 (1.70-12.4) | 2.62 (0.64-10.6) | † |
| Preexisting hypertension | 1.46 (0.88-2.43) | — | — | — |
| Pregnancy characteristics and complications | ||||
| Preeclampsia/eclampsia | 3.31 (1.78-6.43) | 3.18 (1.81-5.72) | 4.41 (1.29-15.0) | 3.02 (1.20-7.61) |
| Gestational hypertension | 1.83 (1.10-3.04) | 1.86 (1.12-3.08) | 0.78 (0.26-2.33) | — |
| Delivery characteristics and complications | ||||
| Pregnancy length | ||||
| Normal gestation (37-42 wk) | 1.00 | 1.00 | 1.00 | 1.00 |
| Preterm gestation (<37 wk) | 2.25 (1.50-3.38) | 2.27 (1.51-3.40) | 2.09 (1.39-3.13)‡ | 1.90 (1.05-3.44) |
| Prolonged gestation (>42 wk) | 0.90 (0.52-1.57) | 0.91 (0.57-1.57) | 0.89 (0.49-1.60)‡ | 1.02 (0.49-2.11) |
| Mode of delivery | ||||
| Spontaneous | 1.00 | 1.00 | 1.00 | — |
| Assisted | 1.38 (0.83-2.28) | 1.41 (0.85-2.34) | 1.29 (0.76-2.20)§ | — |
| Elective cesarean | 2.39 (1.55-3.68) | 2.39 (1.55-3.69) | 2.47 (1.58-3.85)§ | — |
| Emergency cesarean | 2.78 (1.93-4.01) | 2.81 (1.95-4.05) | 2.23 (1.50-3.33)§ | — |
| Stillbirth outcome | 7.42 (3.64-15.1) | 7.57 (3.71-15.4) | 7.17 (3.33-15.4) | 11.9 (5.43-26.1) |
| Postpartum hemorrhage | 1.93 (1.30-2.87) | 1.93 (1.30-2.86) | 1.78 (1.17-2.72) | 2.35 (1.32-4.17) |
| Postpartum acute systemic infection | 4.18 (2.72-6.43) | 4.07 (2.64-6.28) | 3.72 (2.32-5.97) | 3.59 (1.85-6.96) |
| Variable . | IRR (95% CI) . | |||
|---|---|---|---|---|
| MF 1 . | MF 2 . | MF 3 . | MF 3 restricted to spontaneous vaginal/assisted deliveries . | |
| Demographic and lifestyle characteristics | ||||
| Maternal age at delivery | ||||
| Age (for every year increase)* | 1.03 (1.00-1.06) | 1.02 (0.99-1.05) | 1.02 (0.99-1.05) | 1.02 (0.98-1.07) |
| BMI (kg/m2) | ||||
| Normal (18.5-24.9) | 1.00 | 1.00 | 1.00 | 1.00 |
| Underweight (<18.5) | 0.70 (0.21-2.27) | 0.69 (0.21-2.23) | 0.74 (0.23-2.39) | 0.84 (0.19-3.56) |
| Overweight (25-29.9) | 1.35 (0.88-2.07) | 1.36 (0.89-2.09) | 1.21 (0.77-1.90) | 0.67 (0.30-1.46) |
| Obese (30-40) | 2.13 (1.36-3.34) | 2.15 (1.37-3.37) | 1.91 (1.18-3.11) | 2.57 (1.37-4.82) |
| Class 3 obese (≥40) | 7.23 (3.89-13.4) | 7.45 (4.00-13.8) | 6.36 (3.19-12.6) | 11.5 (4.96-26.6) |
| Cigarette smoker | 1.43 (1.03-1.99) | 1.44 (1.04-2.00) | 1.38 (0.97-1.96) | 1.16 (0.71-1.89) |
| Preexisting comorbidities | ||||
| Varicose veins | 3.50 (2.09-5.87) | 3.50 (2.09-5.78) | 3.97 (2.36-6.68) | 4.88 (2.61-9.11) |
| Cardiac disease | 2.67 (1.09-6.53) | 2.59 (1.05-6.33) | 2.78 (1.02-7.53) | 2.69 (0.66-10.9) |
| Inflammatory bowel disease | 4.59 (1.69-12.4) | 4.61 (1.70-12.4) | 2.62 (0.64-10.6) | † |
| Preexisting hypertension | 1.46 (0.88-2.43) | — | — | — |
| Pregnancy characteristics and complications | ||||
| Preeclampsia/eclampsia | 3.31 (1.78-6.43) | 3.18 (1.81-5.72) | 4.41 (1.29-15.0) | 3.02 (1.20-7.61) |
| Gestational hypertension | 1.83 (1.10-3.04) | 1.86 (1.12-3.08) | 0.78 (0.26-2.33) | — |
| Delivery characteristics and complications | ||||
| Pregnancy length | ||||
| Normal gestation (37-42 wk) | 1.00 | 1.00 | 1.00 | 1.00 |
| Preterm gestation (<37 wk) | 2.25 (1.50-3.38) | 2.27 (1.51-3.40) | 2.09 (1.39-3.13)‡ | 1.90 (1.05-3.44) |
| Prolonged gestation (>42 wk) | 0.90 (0.52-1.57) | 0.91 (0.57-1.57) | 0.89 (0.49-1.60)‡ | 1.02 (0.49-2.11) |
| Mode of delivery | ||||
| Spontaneous | 1.00 | 1.00 | 1.00 | — |
| Assisted | 1.38 (0.83-2.28) | 1.41 (0.85-2.34) | 1.29 (0.76-2.20)§ | — |
| Elective cesarean | 2.39 (1.55-3.68) | 2.39 (1.55-3.69) | 2.47 (1.58-3.85)§ | — |
| Emergency cesarean | 2.78 (1.93-4.01) | 2.81 (1.95-4.05) | 2.23 (1.50-3.33)§ | — |
| Stillbirth outcome | 7.42 (3.64-15.1) | 7.57 (3.71-15.4) | 7.17 (3.33-15.4) | 11.9 (5.43-26.1) |
| Postpartum hemorrhage | 1.93 (1.30-2.87) | 1.93 (1.30-2.86) | 1.78 (1.17-2.72) | 2.35 (1.32-4.17) |
| Postpartum acute systemic infection | 4.18 (2.72-6.43) | 4.07 (2.64-6.28) | 3.72 (2.32-5.97) | 3.59 (1.85-6.96) |
MF 1, models are built for each risk factor separately, adjusting for demographic and lifestyle characteristics only; MF 2, as MF 1 and additionally adjusted for preexisting comorbidities; MF 3, as MF 2 and additionally adjusted for pregnancy characteristics and complications.
Age taken as a continuous variable.
No VTE events to perform analysis.
Additionally adjusted for stillbirths.
Additionally adjusted for stillbirths, postpartum infection, and postpartum hemorrhage.