Now that women delay their first pregnancy till their early thirthies, they often experience problems with getting pregnant when they are ready for it, especially when they are having a busy life with a job. Knowing when you are fertile, which is in the days before the egg is releases, is important knowledge if you want to become pregnant. The stress related to not getting pregnant makes things worse. Many IVF treatments could be avoided if women had a simple and reliable method for knowing when they are fertile.