Yes, it is normal for a woman’s menstrual cycles to be irregular when she first starts having her periods. Once her periods are established, normally a woman’s menstrual cycle will be 28-29 days. You figure out the length of your cycle by counting from the first day of one period to the first day of the next period. The time that women bleed, length of menses, is usually 4-8 days. The amount of flow can vary also, but is usually heavier in the early days of menses and lighter toward the end of menses.
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