Thrombophilia and preeclampsia
We would like to contribute a few comments on the pre-eclampsia community guideline (PRECOG).
The presence of antiphospholipid antibodies (aPLs) is associated with pre-eclampsia. However, aPLs have also been described in other clinical settings such as infections or drug administration. Only their persistent presence has a clinical significance and laboratory discrepancies may exist concerning the titer. A single positive result is therefore not necessarily associated with an adverse maternal outcome. In our view, such a situation would not justify specialist referral and furthermore would probably not be cost-effective, considering the high rate of false positive aPLs.
Genetic thrombophilia such as the factor V Leiden may also be a modest but usefull biological marker in improving early prediction of pre- eclampsia. Two meta-analysis provide support for an association of factor V Leiden and pre-eclampsia [1,2]. In the first study , factor V Leiden was associated with a 2.9 fold (95% CI 2.0-4.3) increased risk of severe pre-eclampsia. This association was confirmed recently  with an OR of 1,81 (95% CI 1,14-2,87). We recognize that PRECOG was based on studies published from 1996 to 2002 but guidelines are not meant to be static and we hope that a future update will analyse this issue.
Finally, since there is no single reliable screening test for predicting pre-eclampsia, the development of a risk calculator combining various risk factors (similar to the one used for screening Down’s syndrome) would certainly be a useful tool in today’s growing trend towards predictive medecine.
1. Dudding TE, Attia J. The association between adverse pregnancy outcomes and maternal factor V Leiden genotype : a meta-analysis. Thromb Haemost 2004 ;91 :700-11
2. Lin J, August P. Genetic thrombophilias and preeclampsia : a meta- analysis. Obstet Gynecol 2005 ;105 :182-92
Competing interests: None declared
Competing interests: No competing interests