I read one of those and purchased the ebook - a woman called Beth Kiley. Its all dont drink, dont smoke, have sex when you ovulate, and foods to each and not eat to improve fertility.....................
I now keep getting emails when she thinks of something else - water increases your CM, something about nuts, tomatos and did you know peas are a natural fertility killer for men and women and billions of years ago they used peas as a contraceptive!