Your body communicates with your brain and other parts of your body by way of hormones. Hormones are messengers that tell your body what to do and when to do it.
Your menstrual cycle is divided into three phases, the follicular phase, ovulation and the luteal phase. The first half of your menstrual cycle is known as the follicular phase.
After you ovulate, you begin the second half of your fertility cycle known as your luteal phase. During the first half of your cycle, Follicle Stimulating Hormone (FSH) is produced