The Quarterly Review of Biology. Vaginal fluids in menses mainly contribute water, common electrolytes, organ moieties, and at least 14 proteins, including glycoproteins. Recommendations and Reports. Your hormones control your menstrual cycle. This is called the menstrual cycle. See a doctor for menstrual bleeding that lasts longer than 7 days or for cycles that are shorter than 21 days or longer than 35 days. What controls the menstrual cycle?
In one study a seasonal effect was suspected Blanco et al.
Menstrual-like vaginal bleeding in prepubertal girls: an unexplained condition
What is a typical menstrual cycle like? Spermatogenesis spermatogonium spermatocyte spermatid sperm Oogenesis oogonium oocyte ootid ovum Germ cell gonocyte gamete. The pituitary gland in the brain and the ovaries in the female reproductive tract manufacture and release certain hormones at certain times during the menstrual cycle that cause the organs of the reproductive tract to respond in certain ways. This includes menstrual bleeding, for three or more menstrual cycles, that:. Reproductive Biology and Endocrinology.