Abnormal Uterine Bleeding

Abnormal bleeding at a glance

• Abnormal bleeding is defined as excessive menstrual bleeding, or as bleeding between periods, after sex or after menopause.
• A hormone imbalance is the most common cause of abnormal bleeding, although other causes include pregnancy, miscarriage, some birth control methods, blood clotting disorders, and a number of uterine problems.
• Abnormal bleeding is very common and can occur at any time in life, although certain causes and factors are age related.
• Diagnosis options range from simple techniques such as taking a patient’s medical history, to visual examination of the uterus through a scope.
• Treatments range from hormone medication prescriptions to surgery.

What is abnormal uterine bleeding?

In a normal menstrual cycle, a woman’s uterus discharges the equivalent of a few tablespoons of blood through the vagina over several days. This is normal uterine bleeding. In contrast, abnormal uterine bleeding is defined as bleeding in significant excess of this amount, or as bleeding between menstrual periods, after sex, for longer than usual, or after menopause.

For several reasons, the definition of “normal” menstrual periods and bleeding takes a broad range of factors into account.

A woman’s menstrual cycle begins at the first day of bleeding (the menstruation period) and ends with the first day of the next period. A normal cycle is usually 28 days long, but it is very common for the length of the menstrual cycle to vary over a woman’s reproductive years.

For example, a teenage girl may experience irregular cycles that become more regular with time. As a woman approaches age 35, she may experience increasingly shorter cycles.

As a woman nears and enters menopause (normally in her late 40s and early 50s), she may skip periods all together; at the same time, the bleeding may also become either lighter or heavier.

Taking these factors into account, doctors generally consider menstrual cycles abnormal if they are shorter than 21 days or longer than 35 days, or if there are other irregularities, which may be signs of a number of health conditions.

Causes of abnormal uterine bleeding

For most women, a hormone imbalance is the cause of abnormal uterine bleeding. In these cases, doctors classify the problem as dysfunctional abnormal bleeding (DUB). This kind of bleeding is more common in teens or in women approaching menopause.

Other causes of abnormal uterine bleeding include:

• Pregnancy
• Some birth control methods, including an intrauterine device (IUD) or birth control pills
• Excessive thickening of the uterine lining, called endometrial hyperplasia.
• Problems with blood clotting from disorders such as von Willebrand’s disease and platelet abnormalities
• Uterine fibroids or polyps, irregular growths and benign tumors
• Thyroid problems
• Ectopic pregnancy, in which a fertilized egg does not reach the uterus for normal development
• Miscarriage
• Cancer of the uterus, cervix or vagina

Age-related factors

Abnormal bleeding can occur at any time in life, although certain causes tend to be age related.

• Young girls may experience bleeding before their first period (called menarche) due to trauma and injury, a foreign body, genital irritation, urinary tract problems, or sexual abuse.
• Adolescents often experience abnormal bleeding for several months, or even years, after menarche.
• Young women sometimes do not release an egg from their ovaries (ovulate) during a cycle, creating a hormone imbalance. The body’s estrogen thickens the uterine lining (the endometrium) more than usual, and when the uterus discharges the lining during menstruation (a woman’s period), the bleeding can be quite heavy.

The same hormone imbalance may confuse the body as to when to shed the endometrium, causing spotting between periods.

• Premenopausal women in their 40s and 50s may skip some months of ovulation, causing irregular menstrual flow – some months may bring heavy bleeding, while other months are much lighter than usual. Women in this age group also undergo a thickening of the endometrium. Because this thickening is sometimes a sign of uterine cancer, women in this age group who notice abnormal bleeding should consult with a doctor.
• Post-menopausal women can experience abnormal bleeding as a result of hormone replacement therapy.Other causes after menopause include:
  • Polyps or fibroids
  • Uterine infection
  • Excessive thinning of the tissue lining the vagina and uterus
  • Use of blood thinners and anticoagulants
  • Side effects of radiation therapy
  • Endometrial hyperplasia, or unusual/excessive cell growth in the endometrium
  • Endometrial cancer

Diagnosing abnormal uterine bleeding

Medical professionals have several options for helping to uncover the cause of abnormal bleeding:

A medical history can reveal much about abnormal bleeding. A doctor or nurse practitioner can review symptoms that accompany the bleeding (any fever, pain or vaginal odor), including an increase in bleeding after sex. The doctor or nurse may also want to know about medications the woman is taking, any significant weight changes, any sudden lifestyle shifts such as new diet or exercise programs, and if there is family history of bleeding.

A physical exam by a doctor or nurse may include a pelvic exam and a Pap smear, which may uncover lesions or abnormal cells in the uterus, cervix and vagina.

A transvaginal ultrasound measures the shape and size of the uterus. In this procedure, a small probe is inserted into the vagina. Through the use of sound waves, ultrasound equipment can provide an image of the uterus, measure the thickness of the endometrium, and help determine overall uterine health.

Saline infusion sonography, or sonohysterography (also called a hysterosonogram), is a test in which a transvaginal ultrasound is performed after saline is injected into the uterus. The saline yields better images of the uterus, allowing detection of smaller lesions. The disadvantage is that tissue samples cannot be taken, so additional evaluation may be necessary. This can include hysteroscopy with dilation and curettage (see below).

A dilation and curettage, or D&C, can be done both for diagnosis and treatment. It is a procedure in which the cervix is dilated so that instruments can remove the lining of the uterus. A D&C can halt the bleeding, while the removed lining can be checked in a laboratory for abnormal tissue. A D&C is performed under anesthesia.

A magnetic resonance image (MRI) is sometimes useful for determining whether there are uterine fibroids or other structural abnormalities.

Hysteroscopy involves insertion of a small scope through the cervix and into the uterus. Air or liquid is then injected to expand the uterus and allow a doctor to look inside and also take tissue samples. This procedure is performed under anesthesia and often along with a D&C.

Treatment for abnormal uterine bleeding

There are also numerous treatment options for abnormal bleeding:

Birth control pills can stop the endometrium (uterine lining) from growing too thick, as well as help regulate menstrual periods and reduce menstrual cramping. However, some birth control pills – notably, the progestin-only pill, also known as the “mini-pill” – can actually cause abnormal bleeding in some women.

Progesterone is a hormone produced in the ovary. A synthetic form of progesterone, progestin, can be an effective treatment for women with abnormal bleeding caused by irregular ovulation. Progestin usually comes in a pill form and is taken daily or for 10 to 12 days each month to control vaginal bleeding.

An intrauterine device (IUD) is a small, plastic device inserted into the uterus through the vagina to prevent pregnancy, and can also reduce abnormal bleeding. A progestin-releasing IUD also decreases menstrual bleeding by 40 to 50 percent (or even halting it all together for some women) and can ease menstrual pains. However, an IUD can also be the cause of bleeding, so women already using an IUD and experiencing bleeding should consult a doctor.

Endometrial ablation is a type of surgery that destroys the endometrium (the lining of the uterus.) This kind of surgery removes fibroids and polyps and can be a good option for women who have completed childbearing. There are several technologies for endometrial ablation, including use of heat, cold or a laser.

The newer technologies do not require general anesthesia or a hospital stay and require less recovery time than a hysterectomy, which can be an alternative to ablation. Some women still have bleeding or spotting after endometrial ablation. A few even experience regular periods again. Women who have had this procedure still need to use birth control afterward, despite having low chances of pregnancy.

A hysterectomy, or removal of the uterus, is usually the last option when other treatment attempts have failed. A hysterectomy can be performed through traditional open surgery, in which the uterus is taken out through an incision in the belly, or through what’s known as a minimally invasive procedure. This latter procedure can be performed through a small incision in the vagina or through use of a scope, which may also be robotically assisted.