Table 1.

Prevalence rates for congenital thrombophilia in a European population.

Thrombophilic defect	Prevalence (%)
Factor V Leiden heterozygous	2–7
Prothrombin G20210A heterozygous	2
Antithrombin defect	0.25–0.55
Proteina C deficiency	0.20–0.33
Proteina S deficiency	0.03–0.13
MTHFR C677T homozygous	10