Michaela, from the MS community: Why is MS inactive during pregnancy usually but it causes relapses after birth?
Professor Carolyn Young, a Neurologist: Well, that’s a really good question and it’s actually, I think, a misunderstanding. People think that the birth may cause relapses, but in fact what’s happening is a change in the timing of a relapse that appears to have been destined to happen anyway.
So if we think of the pregnancy year as the nine months when the girl’s pregnant and then the first three months after baby’s born, that’s the 12 months of the pregnancy year. Because in pregnancy people’s immune systems are altered, the relapse rate drops in pregnancy.
When the baby’s born the immune system goes back to the non-pregnancy state and relapses which might have been suppressed during pregnancy then show their head, as it were. So it isn’t that the person has more relapses than they were destined to have, it’s simply changing the timing of when they occur.
Michaela: Right. So there’s no reason that women with MS should think about not having…
Carolyn Young: So yeah, you’re absolutely right. Multiple sclerosis is not an absolute contra-indication against pregnancy. There are some people who sadly have very difficult MS and they should certainly think long and hard not just about the pregnancy, but about the issue of looking after a baby and being able to provide the child with the sort of upbringing that they would want any child of theirs to have, but that’s a rare situation and overall, MS and pregnancy are very, very compatible.