Reports of preliminary findings from a study due to be presented at the American Academy of Neurology meeting in April suggests that the contraceptive pill may be a risk factor for developing MS.
Currently the cause of MS remains unknown but it is thought that the genetic make-up of some people means that MS can be triggered by an environmental factor. There is increasing evidence that smoking may be a significant risk factor and the possible role of an infection such as the Epstein Barr virus, or vitamin D insufficiency remain under investigation.
The new study analysed the health records of 305 women diagnosed with MS or clinically isolated syndrome and looked at their use of birth control up to three years before the onset of MS. They compared these findings to the records of 3,050 women who did not have MS. It has been reported that the preliminary findings of the research indicate an association between contraceptive use and MS. However the author states that the researchers cannot firmly establish causality and that, whilst the findings might explain an increase in the incidence of MS amongst women, they do not intend that young women should avoid birth control to avoid MS.
Previous studies have not supported an important effect of oral contraceptive use on the risk of MS, and indeed have suggested that oral contraceptives might delay the onset of MS.
The full results of the study will be presented at the American Academy of Neurology Meeting from 26th April to 3rd May. The study has not yet been published or reviewed by other experts.
Alvaro A, et al.
Oral contraceptives and the risk of multiple sclerosis: A review of the epidemiologic evidence.
Journal of Neurological Sciences 2009;286:73-75.