Catholic doctrine regarding ligation in extreme cases?

I think I ran across an answer to this sort of question on catholic.com, and they said that, even in a situation where pregnancy can have serious impacts on the mother's health, ligation or any other form of contraception is still unacceptable. Frankly, this is the one issue that prevents me from joining the Catholic Church. I find it problematic that God is so repulsed by contraception that he would rather endanger a woman's life.