Venous thromboembolism and pulmonary embolism events in pregnant women after in vitro fertilisation (IVF) and women with natural pregnancies matched on age and calendar period of delivery. Values are numbers (percentages) of women unless stated otherwise
| Events in relation to pregnancy | IVF pregnancies (n=23 498) | Natural pregnancies (n=116 960) | Proportional hazard regression (95% CI) |
|---|---|---|---|
| Venous thromboembolism: | |||
| Prepregnancy | 71 (0.30) | 415 (0.35) | 0.85 (0.66 to 1.10) |
| Pregnancy and delivery | 99 (0.42) | 291 (0.25) | 1.77 (1.41 to 2.23) |
| Days 43-365 postpartum | 24 (0.10) | 95 (0.08) | 1.29 (0.82 to 2.02) |
| Pulmonary embolism: | |||
| Prepregnancy | 21 (0.09) | 103 (0.09) | 1.04 (0.65 to 1.66) |
| Pregnancy and delivery | 19 (0.08) | 70 (0.06) | 1.42 (0.86 to 2.36) |
| Days 43-365 days postpartum | 3 (0.01) | 26 (0.02) | 0.60 (0.18 to 1.98) |