Michael Voris is somewhat polemical in this video, I think. But watch it anyways, and then watched up the Mic'd Up video that accompanies it. I have been meaning to do a series on this based on some blog posts that went up this summer on Natural Family Planning.
It's not the default, certainly. NFP can be used to plan pregnancies too, and to identify fertility issues. But no one has to use NFP. It's absurd that it's required in certain dioceses and parishes in order for couples to enter the sacrament of marriage, especially since it is good only in certain circumstances and with certain attitudes, not good intrinsically. And, naturally babies should come every two years, maybe plus or minus six months, with breast feeding as much as possible. Alas, it's difficult to breast feed as was done one hundred, one-hundred fifty years ago, and the food products today are so heavily processed. This throws the cycle off quite a bit.
I have some other thoughts that I shall withhold for now...but here it is.