I once heard Doug Phillips say: "The Bible teaches that debt is a curse, and that children are a blessing. Why do we always apply for curses and reject God's blessings?"
I think there is more than just the. "be fruitful and multiply" command that applies here. Scripturally children are a heritage from the Lord. God says, blessed is the man who has his quiver full of them.
Why do we try and avoid children? The common complaint is money. The thing is, we have such an abundance, why not sacrifice and raise a blessing? And why not just trust God? If it is for health, then I understand that, but that is not the case for the majority.
The Lord builds His nation through families. As Christian families, why not have many beautiful blessings, raise them in the fear and admonition of the Lord, and be thankful when the raise up and call us blessed? What is so wrong with this picture that we would invent tools and medicine to avoid it? It is the false teaching in this world, and the lack of Christian world-view among believers. It also stems from the desire for women to be free physically and sexually, not bound to a home full of children and weighed down with that work load.
I challenge everyone to do a search on Margaret Sanger, a full history, and you can see what her motives were for starting planned parenthood.
Blessings