Women’s reproductive system consists of external and internal organs. The external organs, for instance, consists of reproductive organ such as the vulva which covers the opening to the vagina. http://kidshealth.org/parent/general/body_basics/female_reproductive_system.html#

The internal organs such as the fallopian tubes and ovaries are important to creating a baby. For instance, once the sperm fertilizes the egg (released by one of the ovaries) it travels through one of the fallopian tubes. Another internal reproductive organ is called the uterus or womb. The uterus is a muscular, hollow organ located in the pelvis area where the embryo attaches to its’ wall. http://www.asrm.org/uploadedFiles/ASRM_Content/Resources/Patient_Resources/Fact_Sheets_and_Info_Booklets/agefertility.pdf The uterus has many functions whether women are pregnant or not. During pregnancy, the uterus is where the fetus develops for approximately nine months. When women aren’t pregnant, the uterus serves another purpose. It sheds the endometrium.

The endometrium is the lining of the uterus. http://www.asrm.org/uploadedFiles/ASRM_Content/Resources/Patient_Resources/Fact_Sheets_and_Info_Booklets/agefertility.pdf The endometrium typically undergoes changes such as the structure and thickness according to women’s menstrual cycle.http://dictionary.webmd.com/terms/endometrium This means that the endometrium thickens as it prepares for the implantation of the embryo. The reason the endometrium thickens is to provide nourishment for the embryo. When pregnancy does not occur uterus must get rid of the thickened endometrium. To eliminate the endometrium, women go through menstruation. Menstruation is the shedding of the top lining of the uterus accompanied by bleeding.http://www.merckmanuals.com/home/print/sec22/ch241/ch241e.html Usually, when go through the menstruation process every month during their reproductive years unless they become pregnant.

During menstruation, shedding thickened endometrium can lasts for a few days or up to one week. However, for some women this process can cause extremely heavy periods which last for longer than seven days. When this occurs it is called menorrhagia. In women in their 20s to 30s, many conditions such as a hormone imbalance can cause heavy bleeding. With a chemical imbalance, estrogen causes the endometrium to grow until it is too thick causing heavy bleeding.http://familydoctor.org/online/famdocen/home/women/reproductive/menstrual/470.html For women in their 40s to 50s, a thickening of the endometrium and heavy bleeding may be a warning of uterine cancer. http://familydoctor.org/online/famdocen/home/women/reproductive/menstrual/470.html