Before abnormal uterine bleeding is discussed, we will describe normal uterine bleeding. Normal uterine bleeding is defined as menses (periods) occurring every 21-35 days, lasting no longer than seven days and with a blood loss of less than 80 mL with each cycle. It is hard to quantify the amount of bleeding that is occurring, therefore normal bleeding can also be described as not soaking through sanitary protection (pad or tampon) within an hour for more than a few hours.
Any uterine bleeding that does not fall into these ranges is considered abnormal, especially in women between the ages of 20-40 years old. Before and after this age range, variations of menstrual cycles may be normal due to the development or decline of the hormone levels necessary to maintain a normal cycle. Within the definition of abnormal uterine bleeding (AUB) there are other terms that are more precise to the type of bleeding pattern that is occurring. These are defined below:
Menorrhagia = Cyclical bleeding that occurs every 21-35 days but lasts longer than seven days with a loss of greater than 80 mL or soaking through sanitary protection within an hour for more than a few hours.
Oligomenorrhea = Cyclical bleeding that occurs more than every 35 days.
Polymenorrhea = Cyclical bleeding that occurs less than every 21 days.
Amenorrhea = Absence of menses by age 16 or for three cycles or six months in women who had menses previously. If an adolescent has not had menses nor developed breasts or pubic hair by the age of 14, she should seek medical care as well.
Metrorrhagia = Light bleeding that occurs irregularly.
Menometrorrhagia = Heavy bleeding that occurs irregularly.
Intermenstrual Bleeding = Bleeding that occurs in between regular menstrual cycles.
Premenstrual Bleeding = Spotting right before menses begins.
Dysfunctional Uterine Bleeding = Irregular, heavy bleeding that is most commonly due to lack of ovulation.
Postmenopausal Bleeding = Bleeding that occurs after menopause has been established. (Menopause is defined as 12 months of no menses after completion of menstrual cycles.)
- Thyroid disease – Abnormal thyroid hormone levels
- Hyperprolactinemia – Elevated prolactin level
- Polycystic Ovarian Syndrome – Triad consisting of ovaries containing many follicles, oligomenorrhea or amenorrhea, and male hormone excess with possible symptoms of acne, hair growth in a male distribution, balding similar to a man, deepening of voice and/or enlargement of the clitoris
- Stress, Excessive weight loss/Eating disorder, Excessive exercise– Causes changes in hormone levels that affect menstrual cycles
- Thrombocytopenia – Low platelet count
- Von Willebrand’s disease – Deficiency or lack of the Von Willebrand factor in the blood that is important in clotting
Local disease/Anatomic lesions
- Polyps – Overgrowths of the uterine lining that are most often benign, however, cancer cannot be ruled out unless removed or biopsied
- Fibroids– Benign smooth muscle tumor of the uterus.
- Adenomyosis – Cells from the uterine lining that implant into the muscle wall of the uterus causing the uterus to become boggy and inefficient in its muscle contractions to help with blood loss
- Ovarian cysts – May replace normal ovarian tissue and affect ovulation
- Atrophy – When a woman is estrogen deficient, such as during menopause, the lining of the uterine cavity and vagina become thin and “dry”
Pregnancy – Some women may have bleeding in their first trimester and mistakenly associate the bleeding to a period or irregular menses
Cancer – Cancer of the pelvic structures or cancer from other organs spread to the pelvic organs
Medications – Some medications such as contraceptives and blood thinners
Infection – Uterine, cervical or vaginal infection
Trauma – Sexual abuse, foreign bodies, accidents
Dysfunctional Uterine Bleeding – Diagnosis is made from exclusion of any potential causes of AUB
Other less common causes may be discussed by your physician.
How is the cause of Abnormal Uterine Bleeding diagnosed?
A personal history and physical exam are important to help identify signs and symptoms of the potential causes that the patient may not necessarily feel or notice, i.e. enlarged uterus, abnormal thyroid gland, pregnancy, etc.
Pregnancy must be ruled out first. Some women experience bleeding within the first 12 weeks of the pregnancy and mistakenly think that it is their period. A blood or urine pregnancy test is sufficient to confirm whether a pregnancy is present. After pregnancy has been excluded, an endometrial biopsy is usually performed in all women 35 years and older. This biopsy is performed in the office using a very thin catheter that is inserted into the uterine cavity to sample the cavity lining. This sample is sent to a pathologist to examine the tissue for precancerous or cancerous cells. Similarly, a pap smear of the cervix is also obtained in all women to examine the cervical cells for precancerous or cancerous cells. Cervical cultures may be obtained at the time of the pap smear as well to check for cervical or vaginal infections. Blood tests may be ordered to evaluate for various conditions mentioned under the “What is Abnormal Uterine Bleeding?” section above.
Diagnostic imaging may be also required to evaluate AUB. Typically, an ultrasound of the pelvis is performed to rule out any anatomic lesions that can cause AUB. If there is a suspicion of structural abnormalities within the uterine cavity, a hysterosonogram orhysteroscopy may be performed. A hysterosonogram is a procedure performed in the office with a transvaginal ultrasound probe and a small catheter introduced into the uterine cavity that allows instillation of fluid into the cavity. This helps to delineate the uterine cavity and allows better visualization of any intrauterine structural abnormalities than just ultrasound alone. Direct visualization of the uterine cavity can be accomplished by performing hysteroscopy. The advantage of this is that the structure may be accessible for removal or biopsy. Hysteroscopy can be done in the office or as an outpatient surgery in the hospital.
These are the most common forms of testing for abnormal uterine bleeding, however, your physician may require additional testing. This is discussed during a consultation with your physician.
How is Abnormal Uterine Bleeding treated?
Treatment of abnormal uterine bleeding varies depending upon the cause. The possible treatments for the common causes of AUB as listed below:
- Thyroid disease – Treat with thyroid hormone medication to correct the abnormal hormone levels.
- Hyperprolactinemia – Additional workup may be required, however medication is usually a first step to correct the hormone level.
- Polycystic Ovarian Syndrome – Commonly women are overweight and weight loss may help to establish regular ovulatory cycles; if pregnancy is not desired at the current time, OCPs or progesterone withdrawals will help with regularity; if pregnancy is desired, medications are used to induce ovulation.
- Stress, Excessive weight loss/Eating disorder, Excessive exercise – Stress management, diet and nutrition counseling may be effective.
- Thrombocytopenia – A referral to a hematologist is strongly recommended to diagnose an underlying cause and treat the disorder.
- Von Willebrand’s disease – A referral to a hematologist is strongly recommended for treatment recommendations.
Local disease/Anatomic lesions
- Polyps – These are usually removed by hysteroscopy.
- Fibroids – Please see link for Fibroids.
- Adenomyosis – Due to the nature of adenomyosis being a diffuse process within the uterine musculature, the most definitive treatment is a Hysterectomy; birth control pills or other forms of hormonal control may be trialed, but may not have great success; Endometrial ablation may be performed in those patients not desiring future pregnancies, however the rate of success is lower than those women without adenomyosis.
- Ovarian cysts – Please see link for Ovarian Cysts
- Atrophy – Hormone replacement therapy or local estrogen treatment will help.
Pregnancy – Please call your physician or Obstetrician immediately if you are experiencing bleeding during your pregnancy
Cancer – A referral to an Oncologist is strongly recommended for a consultation on treatment and management of any organ cancer
Medications – Changing medications or adjusting dosages may help
Infection – Treatment with antibiotics is usually sufficient
Trauma – Lacerations or trauma may need surgical repair; foreign bodies are removed; if you are being sexually abused, please see a physician for help
Dysfunctional Uterine Bleeding – May be controlled with birth control pills or other forms of hormone control, i.e. contraceptive patch, vaginal ring, hormonal intrauterine device;Endometrial ablation may be effective; definitive treatment is with a Hysterectomy.
Treatment for other less common causes may be discussed by your physician.