Don’t perform screening tests of polymorphisms of factor V (Leiden) and Factor II (G20210A) in unselected patients, like all patients with only one episodes of venous thrombosis, in healthy subjects or in pregnant women with no specific anamnestic signs or before to start a treatment with oral contraceptives.

Type of practice

Laboratory tests



Topic Area

Human Genetics

According to national and international recommendations and guidelines, testing should not be performed outside of specific medical conditions, e.g.: episodes of venous thrombosis at an early age or the presence of strong familial history, with two or more affected relatives in the same branch of the family. The predictive value of these tests is limited. The communication of a possible increase of risk of the carriers can lead to anxiety not motivated and determine the inappropriate use of preventive therapies.


1. Coppens et al. Testing for inherited thrombophilia does not reduce recurrence of venous thrombosis. J Thromb Haemost 2008; 6: 1474-1477.
2. Documento di consenso: Salute della Donna. Prevenzione delle complicanze trombotiche associate all’uso di estro-progestinici in età riproduttiva, Conferenza Nazionale di Consenso,19 febbraio 2009, ISS.
3. Cohn DM, Vansenne F, de Borgie CA, Middeldorp S. Thrombophilia testing for prevention of recurrent venous thromboembolism. Cochrane Database Syst Rev 2012 Dec 12; 12: CD007069.
4. Screening di trombofilia e indicazioni alla profilassi farmacologica in gravidanza. Linee guida della Società Italiana per lo Studio dell’Emostasi e Trombosi (SISET), maggio 2008,

Attention. Please note that these items are provided only for information and are not intended as a substitute for consultation with a clinician. Patients with any specific questions about the items on this list or their individual situation should consult their clinician.