That happens (in a normal 28-day cycle) something like at least half of the days, or even almost all of them. Eggwhite cervical
mucus happens only one, two, or at most three days out of the
menstrual month. It is an indicator that you are about to ovulate (produce an egg). After you ovulate, in about two weeks, a period comes. The function of the first, thin kind of mucus, is to clean your vagina, and to block the entry of sperm.