Womens breasts need alone 5 mg of Iodine a day. On a typical diet we are lucky if it contains 200 mcg daily.
Then we have the ovaries that is actually able to make thyroid hormones.
We are meant for childbearing ; so the nutrients take a different route than it does with men. Estrogen is a key factor here; and today even men get to much of it, due to soy (IMO) PUFAs etc.
I have been rethinking a lot lately; a little Ray Peatish at the moment; even if he doesnt promote Iodine he has some complementary info. Much about estrogen overload; http://raypeat.com/articles/