The menstrual cycle is the process where an egg develops each month and the lining of your womb is prepared for possible pregnancy1
The menstrual cycle is driven by body chemicals called hormones. A cycle is counted from the first day of bleeding (your period) to the first day of your next period.2 The rise and fall of hormonal levels during this time control the menstrual cycle.
What’s happening in your womb?
What’s happening to your hormones?
The menstrual cycle is controlled by a complex interaction of hormones.1 In each cycle, increasing levels of hormones cause the ovary to develop an egg and release it (ovulation).2 The womb lining also starts to thicken.