Absolute and relative rates of VTE by risk factors in the postpartum period
| Variable . | Events . | Rate* . | IRR† (Model 1) . | IRR‡ (Model 2) . |
|---|---|---|---|---|
| Maternal characteristics | ||||
| Maternal age, y | ||||
| 15-24 | 48 | 255 (192-339) | 0.80 (0.57-1.12) | 0.86 (0.62-1.00) |
| 25-34 | 156 | 316 (270-370) | 1.00 | 1.00 |
| 35-44 | 81 | 497 (399-618) | 1.51 (1.15-1.98) | 1.37 (1.23-3.01) |
| Body mass index | ||||
| Underweight (<18.5 kg/m2) | 4 | 145 (54-386) | 0.63 (0.23-1.71) | 0.61 (0.22-1.67) |
| Normal (18.5-24.9 kg/m2) | 88 | 237 (192-292) | 1.00 | 1.00 |
| Overweight (25-29.9 kg/m2) | 48 | 324 (244-429)) | 1.33 (0.93-1.89) | 1.29 (0.90-1.83) |
| Obese (≥30 kg/m2) | 79 | 926 (742-1554) | 3.75 (2.76-5.08) | 3.45 (2.54-4.69) |
| No BMI recorded before conception | 66 | 305 (239-390) | 1.40 (1.01-1.92) | 1.46 (1.06-2.01) |
| Current smokers | 80 | 403 (324-504) | 1.31 (1.01-1.71) | 1.30 (1.00-1.69) |
| Pregnancy-related characteristics and complication§ | ||||
| Mode of delivery | ||||
| Spontaneous | 186 | 281 (243-325) | 1.00 | 1.00 |
| Assisted | 16 | 302 (185-494) | 1.18 (0.70-1.99) | 1.22 (0.73-2.06) |
| Caesarean | 83 | 637 (513-790) | 1.99 (1.52-2.58) | 1.88 (1.44-2.45) |
| Previous live births | ||||
| None | 152 | 318 (271-373) | 1.00 | 1.00 |
| 1 | 75 | 285 (228-358) | 0.81 (0.61-1.08) | 0.82 (0.62-1.09) |
| 2 | 33 | 432 (307-608) | 1.13 (0.77-1.66) | 1.08 (0.73-1.60) |
| 3 or more | 25 | 904 (611-608) | 2.07 (1.34-3.20) | 1.92 (1.22-2.99) |
| Stillbirth | 6 | 2444 (109-5440) | 6.24 (2.77-14.1) | 4.07 (1.73-9.56) |
| Multiple gestation | 7 | 491 (234-1030) | 1.39 (0.65-2.93) | 0.94 (0.43-2.07) |
| Preterm birth | 51 | 854 (649-1124) | 2.69 (1.99-3.65) | 2.28 (1.66-3.14) |
| Preeclampsia/eclampsia | 3 | 705 (227-2188) | 1.84 (0.59-5.78) | 1.17 (0.36-3.77) |
| Obstetric hemorrhage | 10 | 963 (518-1791) | 2.89 (1.53-5.43) | 2.53 (1.34-4.79) |
| Gestational diabetes | 6 | 1013 (455-2255) | 1.97 (0.87-4.45) | 1.68 (0.74-3.82) |
| Gestational hypertension | 10 | 705 (379-1311) | 1.63 (0.85-3.12) | 1.49 (0.78-2.84) |
| Acute respiratory tract infection | 18 | 617 (389-980) | 1.65 (1.02-2.66) | 1.56 (0.97-2.53) |
| Urinary tract infection | 27 | 391 (268-571) | 1.15 (0.77-1.71) | 1.06 (0.71-1.58) |
| Medical comorbidities§ | ||||
| Preexisting diabetes | 4 | 445 (167-1186) | 0.88 (0.33-2.38) | 0.69 (0.25-1.85) |
| Preexisting hypertension | 3 | 113 (36-353) | 0.25 (0.81-0.79) | 0.22 (0.71-0.68) |
| Varicose veins | 25 | 1330 (899-1969) | 3.83 (2.51-5.82) | 3.90 (2.56-5.93) |
| Nephrotic syndrome | 0 | — | — | — |
| Systemic lupus erythematosus | 1 | 2374 (344-16856) | 6.69 (0.95-47.0) | 5.40 (0.76-38.3) |
| Cancer | 5 | 446 (185-1073) | 1.21 (0.49-2.96) | 1.14 (0.46-2.79) |
| Inflammatory bowel disease | 5 | 1514 (630-3638) | 4.56 (1.88-11.0) | 4.07 (1.73-9.57) |
| Cardiac disease | 2 | 2258 (646-10335) | 6.58 (1.63-26.5) | 5.30 (1.30-21.5) |
| Variable . | Events . | Rate* . | IRR† (Model 1) . | IRR‡ (Model 2) . |
|---|---|---|---|---|
| Maternal characteristics | ||||
| Maternal age, y | ||||
| 15-24 | 48 | 255 (192-339) | 0.80 (0.57-1.12) | 0.86 (0.62-1.00) |
| 25-34 | 156 | 316 (270-370) | 1.00 | 1.00 |
| 35-44 | 81 | 497 (399-618) | 1.51 (1.15-1.98) | 1.37 (1.23-3.01) |
| Body mass index | ||||
| Underweight (<18.5 kg/m2) | 4 | 145 (54-386) | 0.63 (0.23-1.71) | 0.61 (0.22-1.67) |
| Normal (18.5-24.9 kg/m2) | 88 | 237 (192-292) | 1.00 | 1.00 |
| Overweight (25-29.9 kg/m2) | 48 | 324 (244-429)) | 1.33 (0.93-1.89) | 1.29 (0.90-1.83) |
| Obese (≥30 kg/m2) | 79 | 926 (742-1554) | 3.75 (2.76-5.08) | 3.45 (2.54-4.69) |
| No BMI recorded before conception | 66 | 305 (239-390) | 1.40 (1.01-1.92) | 1.46 (1.06-2.01) |
| Current smokers | 80 | 403 (324-504) | 1.31 (1.01-1.71) | 1.30 (1.00-1.69) |
| Pregnancy-related characteristics and complication§ | ||||
| Mode of delivery | ||||
| Spontaneous | 186 | 281 (243-325) | 1.00 | 1.00 |
| Assisted | 16 | 302 (185-494) | 1.18 (0.70-1.99) | 1.22 (0.73-2.06) |
| Caesarean | 83 | 637 (513-790) | 1.99 (1.52-2.58) | 1.88 (1.44-2.45) |
| Previous live births | ||||
| None | 152 | 318 (271-373) | 1.00 | 1.00 |
| 1 | 75 | 285 (228-358) | 0.81 (0.61-1.08) | 0.82 (0.62-1.09) |
| 2 | 33 | 432 (307-608) | 1.13 (0.77-1.66) | 1.08 (0.73-1.60) |
| 3 or more | 25 | 904 (611-608) | 2.07 (1.34-3.20) | 1.92 (1.22-2.99) |
| Stillbirth | 6 | 2444 (109-5440) | 6.24 (2.77-14.1) | 4.07 (1.73-9.56) |
| Multiple gestation | 7 | 491 (234-1030) | 1.39 (0.65-2.93) | 0.94 (0.43-2.07) |
| Preterm birth | 51 | 854 (649-1124) | 2.69 (1.99-3.65) | 2.28 (1.66-3.14) |
| Preeclampsia/eclampsia | 3 | 705 (227-2188) | 1.84 (0.59-5.78) | 1.17 (0.36-3.77) |
| Obstetric hemorrhage | 10 | 963 (518-1791) | 2.89 (1.53-5.43) | 2.53 (1.34-4.79) |
| Gestational diabetes | 6 | 1013 (455-2255) | 1.97 (0.87-4.45) | 1.68 (0.74-3.82) |
| Gestational hypertension | 10 | 705 (379-1311) | 1.63 (0.85-3.12) | 1.49 (0.78-2.84) |
| Acute respiratory tract infection | 18 | 617 (389-980) | 1.65 (1.02-2.66) | 1.56 (0.97-2.53) |
| Urinary tract infection | 27 | 391 (268-571) | 1.15 (0.77-1.71) | 1.06 (0.71-1.58) |
| Medical comorbidities§ | ||||
| Preexisting diabetes | 4 | 445 (167-1186) | 0.88 (0.33-2.38) | 0.69 (0.25-1.85) |
| Preexisting hypertension | 3 | 113 (36-353) | 0.25 (0.81-0.79) | 0.22 (0.71-0.68) |
| Varicose veins | 25 | 1330 (899-1969) | 3.83 (2.51-5.82) | 3.90 (2.56-5.93) |
| Nephrotic syndrome | 0 | — | — | — |
| Systemic lupus erythematosus | 1 | 2374 (344-16856) | 6.69 (0.95-47.0) | 5.40 (0.76-38.3) |
| Cancer | 5 | 446 (185-1073) | 1.21 (0.49-2.96) | 1.14 (0.46-2.79) |
| Inflammatory bowel disease | 5 | 1514 (630-3638) | 4.56 (1.88-11.0) | 4.07 (1.73-9.57) |
| Cardiac disease | 2 | 2258 (646-10335) | 6.58 (1.63-26.5) | 5.30 (1.30-21.5) |
Absolute rate calculated as per 100 000 person-years.
Adjusted for age, parity, BMI, and smoking status when not stratified by them.
Adjusted for age, parity, BMI, mode of delivery, pregnancy length, obstetric hemorrhage, varicose veins, IBD, cardiac disease and smoking status when not stratified by them.
IRR compared with women without risk factor under study.