i agree with Tet J. about Taking Charge of YOur Fertility, author, Toni Weschler. gratitude for this book.
Ms. Weschler provides women with a method of self observation that allows women to realize if and when they are ovulating.
Ms. Weschler calls her method FertilityAwareness. it is very, very different than the rhythm method.
the Fertility Awareness method of observation maybe used to optimize chances of becoming pregnant or to avoid pregnancy.