Breast feeding as a contraceptive practice sometimes worked; sometimes didn't. But a lot of families with l0 or l2 children would show ages generally about two years apart. Of course, there was nothing foolproof about this and there were abortions that no one ever knew about and certainly didn't discuss. Sometimes in a gap between ages, there have been miscarriages and infant deaths. My grandmother who was born 121 years ago told me the safe way was to keep both feet in a jug. And when a woman had a child at a time somewhat unexpected, she said that person had "lost her notched stick." ~~ Folklorically, Dixie