Menstrual synchrony by chance when there is menstrual cycle variability. Yang and Schank argued that when there is cycle variability (i.e., either women have irregular cycles, have cycles of different frequencies, or both), most women will have the opportunity to experience synchrony even though it is a result of cycle variability and not a result of a mechanism such as the exchange of pheromones. For example, consider two women A and B. Suppose A has menstrual cycles that are 28 days long and B has cycles that are 30 days long. Suppose further that when A and B become close friends, B
Menstrual cycle enhanced during the luteal phases of the menstrual cycle. This is due to the higher metabolic demand during this phase. In particular, women tend to show a cravings for chocolate, with higher cravings during the luteal phase. Females with premenstrual syndrome (PMS) report changes in appetite across the menstrual cycle more than non-sufferers of PMS, possibly due to their oversensitivity to changes in hormone levels. In women with PMS, food intake is higher in the luteal phase than follicular. The remaining symptoms of PMS, including mood changes and physical symptoms, also occur during the luteal phase. No difference for preference