Endometrial polyps are benign localized lesions of the endometrium, which are commonly seen in women of reproductive age. Some may be precancerous or cancerous. They usually occur in women in their 40s and are rare in women under 20 years of age.
The main difference between uterine polyps and uterine fibroids is that fibroids are composed of muscle tissue and polyps are made of endometrial tissue.
No definitive cause of endometrial polyps is known, but they appear to be affected by hormone levels and grow in response to circulating estrogen. Risk factors include obesity, high blood pressure and a history of cervical polyps. Taking tamoxifen or hormone replacement therapy can also increase the risk of uterine polyps.
Endometrial polyps can be solitary or occur with others. They are round or oval and measure between a few millimeters and several centimeters in diameter. They are usually the same red/brown color of the surrounding endometrium although large ones can appear to be a darker red. The polyps consist of dense, fibrous tissue (stroma), blood vessels and gland like spaces lined with endometrial epithelium. If they are pedunculated, they are attached by a thin stalk (pedicle). If they are sessile, they are connected by a flat base to the uterine wall. Pedunculated polyps are more common than sessile ones.
Endometrial polyps can be detected by vaginal ultrasound (sonohysterography), hysteroscopy and dilation and curettage. Detection by ultrasonography can be difficult, particularly when there is endometrial hyperplasia (excessive thickening of the endometrium).
Although treatments such as hysteroscopy usually cure the polyp concerned, recurrence of endometrial polyps is frequent. Untreated, small polyps may regress on their own.
Endometrial polyps are usually benign although some may be precancerous or cancerous. About 0.5% of endometrial polyps contain adenocarcinoma cells.
It is believed that endometrial polyps may have an adverse effect on fertility and fertility treatment outcome.
The specific reason that polyps affect fertility is unknown, but polyps may create an inflammatory reaction inside the uterine cavity or cause irregular bleeding at the time of implantation. These effects would create a hostile environment for the implanting embryo and possibly prevent pregnancy or potentially cause miscarriages.
There is no way to prevent uterine polyps but endometrial resection proved effective in preventing their recurrence.
They often cause no symptoms. Where they occur, symptoms include irregular menstrual bleeding, bleeding between menstrual periods, excessively heavy menstrual bleeding (menorrhagia), and vaginal bleeding after menopause. Bleeding from the blood vessels of the polyp contributes to an increase of blood loss during menstruation and blood "spotting" between menstrual periods, or after menopause. If the polyp protrudes through the cervix into the vagina, pain (dysmenorrhea) may result.
Alternative therapies such as naturopathic medicine may help in shrinking the size of polyps.
Certain hormonal medications, including progestins and gonadotropin-releasing hormone agonists, may lessen symptoms of the polyp.
Endometrial polyps can be surgically removed using curettage with (polypectomy) or without hysteroscopy. When curettage is performed without hysteroscopy, polyps may be missed. To reduce this risk, the uterus can be first explored using grasping forceps at the beginning of the curettage procedure. Hysteroscopy involves visualising the endometrium (inner lining of the uterus) and polyp with a camera inserted through the cervix. If it is a large polyp, it can be cut into sections before each section is removed. If cancerous cells are discovered, a hysterectomy (surgical removal of the uterus) may be performed. A hysterectomy would usually not be considered if cancer has been ruled out. Whichever method is used, polyps are usually treated under general anesthetic.
However, surgical resection of endometrial polyps is recommended in infertile patients prior to treatment in order to increase natural conception or assisted reproductive pregnancy rates.
Polyps can increase the risk of miscarriage in women undergoing IVF treatment. If they develop near the fallopian tubes, they may lead to difficulty in becoming pregnant. There is mixed evidence regarding the resection of newly diagnosed endometrial polyps during ovarian stimulation to improve the outcomes of fresh in vitro fertilization cycles.
An obstruction prevents the egg or sperm from traveling down the tube, thus making fertilization impossible.
Cancer that arises from the endometrium, the lining of the uterus.
Light or infrequent menstrual ﬂow at intervals of 39 days to 6 months or 5–7 cycles in a year.
A blockage of both fallopian tubes.
A condition of blocked passage through one of the Fallopian tubes.
Two very fine tubes that transport sperm toward the egg, and allow passage of the fertilized egg back to the uterus for implantation.
The uterus is the largest and major organ of the female reproductive tract that is the site of fetal growth and is hormonally responsive
Cells composing an inner layer of the uterine lining.
A membrane that forms the upper layer of endometrium that lines uterine cavity, in which fertilized eggs are implanted.
The innermost layer of uterus forming the uterine lumen where the implantation of an oocyte happens.
The primary female sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics.
The very early stage of pregnancy at which the embryo adheres to the wall of the uterus.
Small, elongated tumors that grow on the cervix and that are the most common cause of intermenstrual vaginal bleeding.
An elevated blood pressure, clinically defined as at or greater than 140/90 (systolic/diastolic) mmHg.
Intrauterine death of an embryo or a fetus of less than 500g in mass or before 20 weeks of gestation.
A medical condition of excess body fat that can have a negative effect on health, leading to reduced life expectancy and other health problems.
The period directly preceding and then directly following menopause, usually beginning at a mean age of 45.5-47.5 years.
The period in a woman’s life following her last menstrual period, characterised by permanent infertility.
Abnormally heavy or prolonged bleeding in menstrual periods.
The failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse.
The medical term for infrequent, often light menstrual periods (intervals exceeding 35 days).
Bleeding that occurs irregulary between the menstrual period.
Irregular menstruation is a menstrual disorder whose manifestations include irregular cycle lengths as well as metrorrhagia
Dysmenorrhea is a pain during menstruation. It is the most common menstrual disorder.
Irregular intermenstrual bleeding including postcoital bleeding.
A procedure performed to remove the uterine lining or other tissues in the uterine cavity, for either diagnostic or therapeutic purposes.
Process by which a woman donates eggs for purposes of assisted reproduction or biomedical research.
Surgical removal of the uterus.
A micromanipulative fertilization technique in which a single sperm is injected directly into an egg.
Surgical treatment of removal of endometrial polyps preserving the uterus.
The procedure in which a man (sperm donor) provides his sperm for fertility treatment.
A process in which an egg is fertilised by sperm outside the body: in vitro. Own or donated gametes may be used.