Explanation:
Menstruation is the cyclic changes taking place in women every month which involves the sloughing of the uterine walls.
The menstrual cycle involves the coordination of two-cycle: the ovarian cycle and the uterine cycle.
The menstrual cycle is controlled by the gonadotrophin hormones which are the Luteinizing hormone (LH) and the Follicular stimulating hormone (FSH) and ovarian hormones which are: progesterone and estradiol.
The level of these hormones during each phase are:
1. Follicular phase / proliferative phases- Estradiol level increases/ FSH level declines
2. Ovulation- LH hormone level at the peak, estrogen level at the peak
3. Luteal phase/ secretory phase- Progesterone and estrogen level elevates / LH and FSH level declines