Understanding a 21-Day Menstrual Cycle: What to Know

Question
please im 26yrs.what is associated with having menstral cycle every 21 days.Do i have a safe period in anyway inorder to have sex without getting pregnent?

Answer
naa;

from puberty through menopause,most women cycle through a complex monthly process of hormonal fluctuations and bodily changes.
designed to enable them to bear children,the process most often ends in the shedding of the uterine lining known as menstruation.

catherine;