endocrine
the Endocine system.
It is important to know the roles of each system in the body. The reproductive and the endocrine system is the cause of the onset of the menstrual cycle.
Usualy somewhere between 11 and 15.
Hormones are responsible for the onset of menses. When the body produces enough hormones, the menstrual cycle begins.
purberty for girls around whenever they're in 6th grade
menarche; 12
Bloating and tenderness, cramps in the abdomen, headaches, irritability and ultimately vaginal bleeding are all signs of the onset of the menstrual cycle.
Menarche is the first menstrual flow onset of puberty in girls while menopause is the time when ovaries of a woman stop releasing eggs.
Yes it can, if you do not ovulate, you might not have a period that month.
Yes. Just happened to me; stress in general can cause an early/missed/late period because your emotions are tied into your hormones.
Menarche