A sessile mass in the endometrium or more simply put, an overgrowth of tissue in the inner lining of the uterus is known as a uterine polyp or endometrial polyp as it is also known.
Since a normal uterine or endometrial lining is required for a successful pregnancy, uterine polyps can be the cause of infertility or miscarriage.
A uterine polyp is a bulb like structure and is soft as opposed to uterine fibroids which are usually bigger as well as harder, being made of muscle tissue. These occur very commonly among women and according to some estimates, one in four women have them.
One of the common symptoms of uterine polyps is excessive bleeding from the uterus, however many women do find that they experience no symptoms.
Very heavy menstrual bleeding, spotting between periods, bleeding occurring after sexual intercourse or bleeding after menopause are symptoms of uterine polyps.
Sometimes there may be bleeding from the polyps themselves, which may cause excessive bleeding and when the growth of the polyp actually is big enough to protrude outward and into the vagina, there is likely to be excessive period pain as well.
Though the reason why uterine polyps are formed is not clearly understood, their formation is thought to be connected to the hormone estrogen. This is the reason that women of ages 40 to 50 (when they are most likely to be encountering menopause and major hormonal changes in the body) are the prime targets for uterine polyps.
Also the risk of developing them increases with women who are obese or those that are or have been taking anti estrogen drugs such as tamoxifen.
Other factors that are thought to contribute to women’s risk of developing uterine polyps are high blood pressure and cervical polyps though this link is disputed by some studies.
The reason that uterine polyps can and often do cause infertility is that they act as a kind of natural IUD (intra uterine device) which prevents the egg from implanting into the endometrial wall after it is fertilized.
Also the polyps could be positioned near the area where the fallopian tube is connected with the uterus which will typically make disable the sperm from entering the uterus.
The connection between polyps and infertility is strong and it has been observed that women who had their uterine polyps removed were able to get pregnant thereafter.
A regular ultrasound may not be able to detect a uterine polyp and so it is usually necessary to do a vaginal ultrasound to detect it.