Types of Natural Family Planning: Fertility Awareness Methods: 6: A woman purchases a circle of beads that helps her predict fertile days The first bead on the ring is red and marks the first day of her menstrual flow; this is followed by six brown beads which indicate "safe" days. The woman advances one bead per day during the month. If she reaches a dark brown bead (appears on the 27th day) before she begins her next menses, her cycle is too short for the method to be reliable. If she reaches the end of the string of beads (32 days) before menses, she knows her cycle is too long for the method to be reliable. Advantage(s): Easy to use Disadvantage(s): Needs funds for the beads, Requires motivation, cooperation, ineffective in the prevention of STDs