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In a strongly worded paper, Creinin et al argue that "screening for Factor V Leiden mutation before prescribing combination oral contraceptives is not a cost-effective use of US health care dollars" [Creinin, M.D. et al (1999) Fertil Steril 72, 646-651] (see references on Thrombophilia page for background information). Using the current cost of testing (which involves testing for APC resistance followed by a DNA-based mutation test for those whose APC resistance result suggests they likely to be mutation carriers), the sensitivity and specificity of this testing regimen, the estimated prevalence of the factor V Leiden mutation in the major ethnic groups in the US, and taking into account that some thromboembolic deaths in mutation carriers will occur anyway, regardless of contraceptive use, they calculate an annual cost of around $300 million to prevent one contraceptive-related death due to the factor V Leiden mutation in the US population as a whole. The annual cost in the white ethnic group, where the mutation prevalence is highest, was estimated at $170-$210 million. Screening would result in withholding the combined pill from more than 90,000 mutation carriers to prevent the death of one.

Comment: Although these results apply to the US population, they are broadly in line with previous reports from the UK. A Development and Evaluation Committee report published in 1996 concluded that the case for factor V Leiden screening in potential users of the combined oral contraceptive pill was weak, even if screening were to be restricted to women whose family history indicated that they were at increased risk. Alternative contraceptive choices such as the progesterone-only pill are readily available to such women. In high-risk women who have already experienced a thromboembolic event, knowledge of mutation status makes no difference to clinical management. There are also potential costs associated with discouraging the use of a contraceptive of choice in the large group of mutation carriers that screening would identify. For example, reduced compliance could make unplanned pregnancy more likely, and that in itself would increase the risk of thromboembolic events.