I've been getting them a lot in the last few weeks. Hormonal from the pregnancy dr has said. I spoke to my cousin who's a naturopath and she's put me on a magnesium supplement. Bioceuticals muscleze. It's a powder so absorbed quickly. Taken regularly she says it can reduce frequency and severity of migraines. I haven't had one since I started taking it four days ago.
It won't help while you're in the midst though. Sunglasses, lots of water and panadeine is all that helps me. Sleep if I have someone who can watch the kids!!