Menstruation

Menstruation is a periodic recurrent separation of the lining of the uterus (endometrial) and vaginal bleeding that occurs in a woman when she is not pregnant. Menstruation usually lasts 2-7 days, while the average length of the menstrual cycle is generally considered to be 28 days. Menstrual cycle has two phases:
1. Follicular: day 1 to 14, from the beginning of menstruation to the day before ovulation – estrogen, testosterone, luteinizing hormone LH, follicular stimulating hormone FSH
2. Ovulation: 14th day, release of the mature egg occurs approximately on the 14th day due to the increase in LH and FSH during the previous day. After release, the egg gets into the fallopian tube where fertilization can occur if sperm is present. If it is not fertilized, after approximately 24 hours it falls apart. After releasing the egg, the follicle is sealed and it is called a yellow body.
3. Luteal: day 15 to 28, from ovulation to the day before bleeding starts again – progesterone