The cycle reproductive changes in females is marked my the menstrual cycle.during which some cells, unclotted blood from ruptured blood vessels, other fluids and the uterine endometrium is released through the cervix and vagina.

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The Menstrual Cycle 25 February 2003 George Beard

The cycle reproductive changes in females is marked my the menstrual cycle.during which some cells, unclotted blood from ruptured blood vessels, other fluids and the uterine endometrium is released through the cervix and vagina.

Each menstrual cycle occurs every 28 days and lasts for 4-5 days. an ovum is released from the ovary (ovulation) about once every 4 weeks.

The menstrual cycle (of 28 days) is generally divided into four parts.. or phases , with major events occurring in each phase. The 4 phases are:

(1) The menstrual (destructive) phase

The menstrual phase. The uterus lining (i.e., endometrium) and its blood vessels slough off , and is discharged with blood, mucus, cell debris and other fluid as the menses , through the vagina. This may last for 4-5 days. Menses occur when fertilization does not take place.

(2) The proliferative (follicular) phase

The proliferative phase occurs between the end of menses, and ovulation. In this phase, under the stimulation of estrogen, the uterine endometrium undergoes a process of growth (proliferation) and a new thick endometrium is formed. In the ovary, the follicle begins to develop