Incidence (absolute risk) of venous thromboembolism in pregnancy and puerperium associated with thrombophilic risk factors
| Coagulation defect . | Probability of thrombosis during pregnancy and puerperium* <35 years (basic risk 1:741) . | Probability of thrombosis during pregnancy and puerperium* ≥35 years (basic risk 1:483) . | ||
|---|---|---|---|---|
| % . | 95% CI . | % . | 95% CI . | |
| Genetic defects† | ||||
| FVL heterozygous | 0.5 | 0.23-0.72 | 0.7 | 0.35-1.11 |
| FVL homozygous | 2.2 | 0.0-9.9 | 3.4 | 0.0-14.87 |
| Prothrombin G20210A heterozygous | 0.4 | 0.01-0.78 | 0.6 | 0.02-1.20 |
| FVL and prothrombin G20210A (compound heterozygous) | 5.5 | 0-21.92 | 8.2 | 0.0-31.97 |
| Antithrombin deficiency (activity) | ||||
| Mild deficiency (cutoff <90%) | 0.2 | 0.05-0.32 | 0.3 | 0.07-0.50 |
| Severe deficiency (cutoff <60%) | 6.1 | 0.0-68.16 | 9.0 | 0.0-98.4 |
| Protein C deficiency (activity) | ||||
| Mild deficiency (cutoff <76%) | 0.3 | 0.05-0.53 | 0.4 | 0.077-0.80 |
| Severe deficiency (cutoff <50%) | 0.7 | 0.0-2.90 | 1.1 | 0.0-4.43 |
| Protein S deficiency (activity) | ||||
| Mild deficiency (cutoff <56%) | 0.3 | 0.0-0.66 | 0.5 | 0.0-1.01 |
| Severe deficiency (cutoff <40%) | 0.7 | 0.0-2.14 | 1.0 | 0.0-3.26 |
| Free protein S deficiency (concentration) | ||||
| Mild deficiency (cutoff <57%) | 0.3 | 0.03-0.61 | 0.5 | 0.04-0.93 |
| Severe deficiency (cutoff <40%) | 1.0 | 0.0-3.03 | 1.5 | 0.0-4.61 |
| Coagulation defect . | Probability of thrombosis during pregnancy and puerperium* <35 years (basic risk 1:741) . | Probability of thrombosis during pregnancy and puerperium* ≥35 years (basic risk 1:483) . | ||
|---|---|---|---|---|
| % . | 95% CI . | % . | 95% CI . | |
| Genetic defects† | ||||
| FVL heterozygous | 0.5 | 0.23-0.72 | 0.7 | 0.35-1.11 |
| FVL homozygous | 2.2 | 0.0-9.9 | 3.4 | 0.0-14.87 |
| Prothrombin G20210A heterozygous | 0.4 | 0.01-0.78 | 0.6 | 0.02-1.20 |
| FVL and prothrombin G20210A (compound heterozygous) | 5.5 | 0-21.92 | 8.2 | 0.0-31.97 |
| Antithrombin deficiency (activity) | ||||
| Mild deficiency (cutoff <90%) | 0.2 | 0.05-0.32 | 0.3 | 0.07-0.50 |
| Severe deficiency (cutoff <60%) | 6.1 | 0.0-68.16 | 9.0 | 0.0-98.4 |
| Protein C deficiency (activity) | ||||
| Mild deficiency (cutoff <76%) | 0.3 | 0.05-0.53 | 0.4 | 0.077-0.80 |
| Severe deficiency (cutoff <50%) | 0.7 | 0.0-2.90 | 1.1 | 0.0-4.43 |
| Protein S deficiency (activity) | ||||
| Mild deficiency (cutoff <56%) | 0.3 | 0.0-0.66 | 0.5 | 0.0-1.01 |
| Severe deficiency (cutoff <40%) | 0.7 | 0.0-2.14 | 1.0 | 0.0-3.26 |
| Free protein S deficiency (concentration) | ||||
| Mild deficiency (cutoff <57%) | 0.3 | 0.03-0.61 | 0.5 | 0.04-0.93 |
| Severe deficiency (cutoff <40%) | 1.0 | 0.0-3.03 | 1.5 | 0.0-4.61 |
The results for noncarriers in each separate analysis were between 0.105% for analyses with high prevalence (heterozygous FVL) and 0.20% for analyses with low prevalence (homozygous FVL).
These categories are exclusive; ie, to be included in one of the groups, subjects must display the exact genetic constellation. This leads to, for example, individuals with compound heterozygous FVL and prothrombin G20210A to be excluded from both the heterozygous FVL and the heterozygous prothrombin G20210A groups and vice versa.