In the following audio from a Catholic priest, we learn that God created marriage for two specific purposes:
1. For the procreation and education of children.
2. And that God intends that men and women offer mutual help and comfort in a cruel world, and a remedy for concupiscence.
Pope Francis says there are "so many ways that are licit and that have helped this." That is, there are so many ways to "help" you from having kids.
I don't know of those "many ways" that our Holy Father is referring to. I know that the birth control pill as well as abortion are grave sins. I do know that Natural Family Planning is a tool that can be used in grave circumstances. But I also know that Natural Family Planning is not Catholic Birth Control--just another form of birth control to be used to limit your family's size per your convenience. No, we are still to be open to God's plan.
This video is called The Sanctity of Marriage: The Duty of Motherhood vs the Abuses of NFP
I continue to forget who this priest is, but he's great.