A short period of time, after the onset of puberty. The first mature eggs starts to be released from the ovaries during menstruation. Menstruation may first occur during the start of puberty in women, it may start as early as 8 years old and can start late as 16 years old. Menstruation is the process wherein not fertilized eggs are being broken down and released from the body.
The endocrine system is made of glands that secrete hormones. These hormones help regulate the organs and cells activity. The hormones among other things control your metabolism.
