Know When to Say When

God blessed them; and God said to them, "Be fruitful and multiply, and fill the earth, and subdue it; and rule over the fish of the sea and over the birds of the sky and over every living thing that moves on the earth." (Genesis 1:28, NASB) Many religious traditions cite Genesis 1:28 as God's commandment to mankind not to employ birth control of any kind. But isn't it about time we declared mission accomplished on this one?