Pimples are fond of camping out on our skin at the WORST times. Take our periods: Many women experience an especially stubborn type of breakout like clockwork every month. Blame the hormones.
About two weeks before menstruation, your body increases estrogen and progesterone to prepare the uterus for pregnancy. During this time, production of prostaglandins—the hormone-like substances produced by the uterine lining that cause the uterus to relax and contract increases.