New research suggests that oestrogen may increase susceptibility to seizures.
However, researchers at Northwestern University in Chicago have been keen to point out that, "oestrogen does not cause seizures," according to the report's senior author, Catherine Woolley.
"This change could promote seizure activity… if something else is already wrong with the circuit", adding that women taking oestrogen as part of a hormone replacement therapy "needn't panic" as the hormone does not cause seizures outright, it only increases the chance of a seizure in someone who is already susceptible to them.
The report, which is to be published in Proceedings of the National Academy of Sciences , shows how when rats were treated with oestrogen, the majority of the animal's hippocampal brain cells developed links to more than one other cell. These increased number of links between cells would increase the chance of a seizure if a trigger exists.
Woolley also commented on the research from the perspective of catamenial epilepsy, a seizure pattern linked to a women's menstrual cycle.
"Neurologists who study clinical populations have shown that in about 30 per cent of women with epilepsy, there is at least a doubling of average daily seizure frequency during phases of the menstrual cycle when oestrogen is high and progesterone is low" she said.