Menstrual cycle occur as a result of adopting a restricted diet, as well as engaging in a high amount of exercise. Finally, the cycle is affected more by a vegetarian diet compared to a non-vegetarian diet. Studies investigating effects of the menstrual cycle on alcohol consumption have found mixed evidence. However, some evidence suggests that individuals consume more alcohol during the luteal stage, especially if these individuals are heavy drinkers or have a family history of alcohol abuse. The level of substance abuse increases with PMS, mostly with addictive substances such as nicotine, tobacco and cocaine. One theory behind this suggests this
Breast development lactation by prolactin. Expression of the PRLR in breast tissue may increase by as much as 20-fold when estrogen and progesterone levels drop upon childbirth. With suckling from the infant, prolactin and oxytocin are secreted and mediate milk production and letdown, respectively. Prolactin suppresses the secretion of LH and FSH, which in turn results in continued low levels of estrogen and progesterone, and temporary amenorrhea (absence of menstrual cycles) occurs. In the absence of regular, episodic suckling, which keeps prolactin concentrations high, levels of prolactin will quickly drop, the menstrual cycle will resume and hence normal estrogen and progesterone levels