1. Safe contraception is only suitable for women with the laws of menstrual cycle.
2. Because women&39;s physiological cycle will be affected by emotions and diseases, the rate of safety contraception will be high, and it is recommended to use it with other contraceptive methods.
3. Safe contraception is not suitable for women&39;s menstrual cycle, higher than 35 days, postpartum or lactating women.
4. Before the safety period contraception, it is recommended to record the menstrual cycle in the second half of the year to understand the rule of menstruation.
5. In addition to calculating the safety period, the ovulation date should also be determined in combination with measurement of the basic body gently observing leucorrhea changes in order to better judge the safety period of contraception.
