Menstrual cycle be noticed by women practicing fertility awareness. The secretory phase is the final phase of the uterine cycle and it corresponds to the luteal phase of the ovarian cycle. During the secretory phase, the corpus luteum produces progesterone, which plays a vital role in making the endometrium receptive to implantation of the blastocyst and supportive of the early pregnancy, by increasing blood flow and uterine secretions and reducing the contractility of the smooth muscle in the uterus; it also has the side effect of raising the woman's basal body temperature. While some forms of birth control do not affect the
Menstrual synchrony Menstrual synchrony Menstrual synchrony, also called the McClintock effect, is an alleged process whereby women who begin living together in close proximity experience their menstrual cycle onsets (the onset of menstruation or menses) becoming more synchronized together in time than when previously living apart. "For example, the distribution of onsets of seven female lifeguards was scattered at the beginning of the summer, but after 3 months spent together, the onset of all seven cycles fell within a 4-day period." Martha McClintock's 1971 paper, published in "Nature", says that menstrual cycle synchronization happens when the menstrual cycle onsets of two or