Recent use of oral contraceptives and current pregnancy may lower the risk of developing MS, while the postpartum period may be a time of higher risk of MS onset, new research suggests.

Estrogen was found to delay the onset and change the progress of a disease similar to MS in animals in earlier research. This led to the hypothesis that oral contraceptives containing estrogen might affect risk or alter the course of the disease in humans.

Similarly, a woman's risk might be lower during pregnancy and higher during the postpartum period, during which times profound hormonal changes are known to occur, according to background information in the article.

40 Percent Lower

Using a research database that includes medical and pharmacy records for three million Britons,