The concept refers to the infertile window in a woman’s menstrual cycle, often estimated using a fertility awareness method or a period tracking application. These are the days when the likelihood of conception is very low. The calculation typically involves identifying the estimated ovulation date and then determining the days before menstruation begins and the initial days after menstruation concludes, when pregnancy is unlikely to occur.
Understanding and utilizing information regarding these days offers several advantages. For individuals not seeking pregnancy, it provides a means of natural family planning, although its effectiveness depends on strict adherence to calculations and individual cycle variability. Historically, tracking menstrual cycles and fertile windows has been a significant aspect of reproductive health awareness, predating modern contraceptive methods. This knowledge empowers women to take control of their reproductive health and make informed decisions.