How many days after a girl’s period is the safe period? With the improvement of living standards, women are paying more and more attention to their own health issues. In sexual life, the safety period is one of the important protective measures. So how many days after a girl’s period is the safe period? This article will elaborate on four aspects to help women better master the knowledge of safe period. Characteristics of the menstrual cycle The menstrual cycle is a physiological phenomenon after the female body has been adjusted. The length of the cycle varies from person to person, usually between 28-35 days. Some women have shorter menstrual cycles, only 21 days, but some women have menstrual cycles longer than 35 days.