Absolute rate of VTE per 100 000 pregnancies and NNT
| Risk factors . | 1-3 wk postpartum . | 4-6 wk postpartum . | 7-12 wk postpartum . |
|---|---|---|---|
| BMI ≥ 30 kg/m2 | |||
| Rate (95% CI) | 113 (74-164) | 42 (20-77) | 13 (2-37) |
| NNT (50% RR) | 1771 | 4734 | 15 398 |
| NNT (88% RR) | 1006 | 2690 | 8749 |
| Preeclampsia/eclampsia | |||
| Rate (95% CI) | 155 (67-305) | 78 (21-200) | 40 (48-145) |
| NNT (50% RR) | 1289 | 2557 | 4974 |
| NNT (88% RR) | 733 | 1453 | 2826 |
| Per-term birth | |||
| Rate (95% CI) | 119 (73-183) | 30 (9-69) | 24 (6-62) |
| NNT (50% RR) | 1683 | 6700 | 8249 |
| NNT (88% RR) | 956 | 3807 | 4687 |
| Cesarean section | |||
| Rate (95% CI) | 98 (72-127) | 42 (26-63) | 17 (7-33) |
| NNT (50% RR) | 2050 | 4816 | 11 502 |
| NNT (88% RR) | 1165 | 2737 | 6535 |
| Postpartum hemorrhage | |||
| Rate (95% CI) | 122 (78-181) | 20 (5-51) | 10.2 (1-36) |
| NNT (50% RR) | 1642 | 10 018 | 19 689 |
| NNT (88% RR) | 933 | 5692 | 11 187 |
| Postpartum acute systemic infection | |||
| Rate (95% CI) | 249 (15-38) | 39 (8-114) | 27 (3-96) |
| NNT (50% RR) | 1173 | 5090 | 7479 |
| NNT (88% RR) | 667 | 2892 | 4249 |
| Risk factors . | 1-3 wk postpartum . | 4-6 wk postpartum . | 7-12 wk postpartum . |
|---|---|---|---|
| BMI ≥ 30 kg/m2 | |||
| Rate (95% CI) | 113 (74-164) | 42 (20-77) | 13 (2-37) |
| NNT (50% RR) | 1771 | 4734 | 15 398 |
| NNT (88% RR) | 1006 | 2690 | 8749 |
| Preeclampsia/eclampsia | |||
| Rate (95% CI) | 155 (67-305) | 78 (21-200) | 40 (48-145) |
| NNT (50% RR) | 1289 | 2557 | 4974 |
| NNT (88% RR) | 733 | 1453 | 2826 |
| Per-term birth | |||
| Rate (95% CI) | 119 (73-183) | 30 (9-69) | 24 (6-62) |
| NNT (50% RR) | 1683 | 6700 | 8249 |
| NNT (88% RR) | 956 | 3807 | 4687 |
| Cesarean section | |||
| Rate (95% CI) | 98 (72-127) | 42 (26-63) | 17 (7-33) |
| NNT (50% RR) | 2050 | 4816 | 11 502 |
| NNT (88% RR) | 1165 | 2737 | 6535 |
| Postpartum hemorrhage | |||
| Rate (95% CI) | 122 (78-181) | 20 (5-51) | 10.2 (1-36) |
| NNT (50% RR) | 1642 | 10 018 | 19 689 |
| NNT (88% RR) | 933 | 5692 | 11 187 |
| Postpartum acute systemic infection | |||
| Rate (95% CI) | 249 (15-38) | 39 (8-114) | 27 (3-96) |
| NNT (50% RR) | 1173 | 5090 | 7479 |
| NNT (88% RR) | 667 | 2892 | 4249 |
Absolute rates per 100 000 are based on the number of pregnancies complicated by a particular risk factor (Table 1) divided by VTE events. It does not consider postpartum hemorrhage or postpartum infections as time-varying covariates nor censor postpartum follow-up time after a VTE event.
RR, risk reduction.