I’ve noticed exactly the same thing. Do you need help finding places that have high numbers of women writing for them or help finding good women writers on topics you cover? I’d be happy to make some suggestions about how you could work on this structurally (and promise to not just recommend my friends). Feel free to get in touch. One place to start is VIDA <http://www.vidaweb.org/> which covers gender balance in book reviewing; they will give you a quick shortcut to publications that feature lots of women writers. Also check out the Facebook group “Binders Full of Women Writers,” much of it broken down by categories. So if you are looking, say, for a female journalist who writes about tech, or travel, or health, you could probably find a lot of names there.