Alex and Dani, you're right that educating women is an important step in curbing the runaway growth of the world's population.   But I don't think that's enough if we want to reverse the trend before a lot more environmental devastation occurs.

Attitudes and laws also need to be changed about:
1) men's behavior toward and rights concerning women (e.g., their wives)
and
2) the use of contraception.

If women are educated but societies still condone or even encourage rape and discourage or outlaw the use of contraceptives, a lot of unwanted pregnancies will still occur.