An in-depth report on the causes, treatment, and prevention of menstrual cramps.
Dysmenorrhea; Menorrhagia; Amenorrhea; Cramps; Heavy menstrual bleeding
Menstrual disorders include:
Painful cramps (dysmenorrhea) during menstruation. Primary dysmenorrhea is caused by menstruation itself. Secondary dysmenorrhea is triggered by another condition, such as endometriosis or uterine fibroids.
Heavy bleeding (menorrhagia) includes prolonged menstrual periods or excessive bleeding.
Absence of menstruation (amenorrhea). Primary amenorrhea is considered when a girl does not begin to menstruate by the age of 16. Secondary amenorrhea occurs when periods that were previously regular stop for at least 3 months.
Light or infrequent menstruation (oligomenorrhea) refers to menstrual periods that occur more than 35 days apart. It usually is not a cause for concern, except if periods occur more than 3 months apart.
Treatment for Menstrual Disorders
Treatment options for menstrual disorders include:
Acetaminophen (Tylenol, generic) or nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (Advil, Motrin, generic) and naproxen (Aleve, generic) can help provide pain relief for cramps.
Oral contraceptives (birth control pills) can help regulate menstrual periods and reduce heavy bleeding. Newer continuous-dosing oral contraceptives reduce or eliminate menstrual periods. The LNG-IUS (Mirena), a progesterone intrauterine device (IUD), is often recommended as a first-line treatment for heavy bleeding
- Endometrial ablation is a surgical option. In some cases, hysterectomy may be considered.
In 2012, the Food and Drug Administration (FDA) approved the birth control pill Natazia as a treatment for heavy menstrual bleeding. Oral contraceptives (OCs) are often prescribed to help with menstrual disorders but this is the first OC approved specifically for this purpose. Natazia is a combination OC that contains the estrogen estradiol and the progesterone dienogest.
Menstrual disorders are problems that affect a woman’s normal menstrual cycle. They include painful cramps during bleeding, abnormally heavy bleeding, or not having any bleeding.
Menstruation occurs during the years between puberty and menopause. Menstruation, also called a "period," is the monthly flow of blood from the uterus through the cervix and out through the vagina.
- The uterus is a pear-shaped organ located between the bladder and lower intestine.
- The cervix is the lower portion of the uterus. It has a narrow opening called the os, which connects to the vagina and allows menstrual blood to flow out of the uterus into the vagina.
- The fallopian tubes connect the uterus and ovaries. Ovaries are egg-producing organs that hold 200,000 - 400,000 follicles (from folliculus, meaning "sack" in Latin). These cellular sacks contain the materials needed to produce ripened eggs, or ova. An egg develops within the follicle.
- The endometrium is the inner lining of the uterus. During pregnancy it thickens and becomes enriched with blood vessels to house and nourish the growing fetus.
- If pregnancy does not occur, the endometrium is shed and a woman starts menstruating. Menstrual flow also consists of blood and mucus from the cervix and vagina.
The uterus is a hollow muscular organ located in the female pelvis between the bladder and rectum. The ovaries produce the eggs that travel through the fallopian tubes. Once the egg has left the ovary it can be fertilized and implant itself in the lining of the uterus. The main function of the uterus is to nourish the developing fetus prior to birth.
The Menstrual Cycle
The menstrual cycle is regulated by the complex surge and fluctuations in many different reproductive hormones, which work together to prepare a women’s body for pregnancy. The hypothalamus (an area in the brain) and the pituitary gland control six important hormones:
- Gonadotropin-releasing hormone (GnRH) is released by the hypothalamus.
- GnRH stimulates the pituitary gland to produce follicle-stimulating hormone (FSH) and luteinizing hormone (LH).
- Estrogen, progesterone, and the male hormone testosterone are secreted by the ovaries at the command of FSH and LH.
The menstrual cycle begins with the first day of bleeding. The menstrual cycle is divided into three phases:
- Follicular. The follicular phase begins with menstrual bleeding. At the start of this phase, estrogen and progesterone levels are at their lowest point, which causes the uterine lining to break down and shed. At the same time, the hypothalamus produces GnRH which stimulates production of FSH and LH. As FSH levels increase, they signal the ovaries to produce follicles. Each follicle contains an egg. As FSH levels surge and decline, only one follicle and its egg continues to develop. The maturing follicle releases estrogen, which signals that an egg is mature and ready for egg release (ovulation).
- Ovular. Ovulation marks the halfway point in the menstrual cycle. The ovular phase begins with a surge in LH and FSH levels. Ovulation occurs about 12 - 36 hours after LH levels surge. The follicle bursts and releases the egg, which travels down the fallopian tube to the uterus. (Some women experience a quick dull abdominal pain called mittelschmerz [“middle pain” because it occurs in the middle of the monthly cycle] when the follicle ruptures.) A woman is most likely to get pregnant in the 3 - 5 days before ovulation or the day of ovulation. The egg can live for up to 24 hours after being released.
- Luteal. After releasing the egg, the ruptured follicle closes and forms corpus luteum, a yellow mass of cells that provide a source of estrogen and progesterone during pregnancy.These hormones help the uterine lining to thicken and prepare for the egg’s fertilization. If the egg is fertilized by a sperm cell, it implants in the uterus and pregnancy begins. If fertilization does not occur, the egg breaks apart. The corpus luteum degenerates, and estrogen and progesterone levels drop. Finally, the thickened uterine lining sloughs off and is shed along with the unfertilized egg during menstruation and the menstrual cycle begins again.
Typical Menstrual Cycle
Typical No. of Days
Follicular (Proliferative) Phase
Cycle Days 1 - 6: Beginning of menstruation to end of blood flow.
Estrogen and progesterone start out at their lowest levels.
FSH levels rise to stimulate maturity of follicles. Ovaries start producing estrogen and levels rise, while progesterone levels remains low.
Cycle Days 7 - 13: The endometrium thickens to prepare for the egg implantation.
Cycle Day 14:
Surge in LH. Largest follicle bursts and releases egg into fallopian tube.
Luteal (Secretory) Phase, also known as the Premenstrual Phase
Cycle Days 15 - 28:
Ruptured follicle develops into corpus luteum, which produces progesterone. Progesterone and estrogen stimulate blanket of blood vessels to prepare for egg implantation.
If fertilization occurs:
Fertilized egg attaches to blanket of blood vessels that supplies nutrients for the developing placenta. Corpus luteum continues to produce estrogen and progesterone.
If fertilization does not occur:
Corpus luteum deteriorates. Estrogen and progesterone levels drop. The blood vessel lining sloughs off, and menstruation begins.
Features of Menstruation
Onset of Menstruation (Menarche). The onset of menstruation, called the menarche, typically begins between the ages of 12 - 13 years. Menarche generally occurs 2 - 3 years after initial breast development (breast budding). African-American and Hispanic girls tend to mature slightly earlier than Caucasian girls. A higher body mass index (BMI) during childhood is associated with earlier puberty and menarche. Environmental factors and nutrition may also affect when menstruation begins.
Length of Monthly Cycle. The average menstrual cycle is about 28 days but anywhere from 21 days to 35 days is considered normal. Cycles tend to be longer during the teenage years and they also lengthen when a woman reaches her 40s. Cycle length is most irregular around the time that girls first start menstruating (menarche) and when women stop
Duration of Periods. Most women bleed for around 3 - 5 days but a normal period can last anywhere from 2 - 7 days.
Normal Absence of Menstruation. Normal absence of periods can occur in any woman under the following circumstances:
- Menstruation stops during pregnancy. Some women continue to have irregular bleeding during the first trimester. This bleeding may indicate a miscarriage and requires immediate attention by the doctor.
- When women breast-feed they are unlikely to ovulate. After that time, menstruation usually resumes, and they are fertile again.
- Perimenopause starts when the intervals between periods begin to lengthen, and it ends with menopause itself (the complete cessation of menstruation). Menopause usually occurs at about age 51, although smokers often go through menopause earlier.
There are a number of different menstrual disorders. Problems can range from heavy, painful periods to no periods at all. There are many variations in menstrual patterns, but in general women should be concerned when periods come fewer than 21 days or more than 3 months apart, or if they last more than 10 days. Such events may indicate ovulation problems or other medical conditions.
Dysmenorrhea (Painful Cramps)
Dysmenorrhea is severe, frequent cramping during menstruation. Pain occurs in the lower abdomen but can spread to the lower back and thighs. Dysmenorrhea is usually referred to as primary or secondary.
Primary dysmenorrhea. Primary dysmenorrhea is cramping pain caused by menstruation. The cramps occur from contractions in the uterus and are usually more severe during heavy bleeding.
Secondary dysmenorrhea. Secondary dysmenorrhea is menstrual-related pain that accompanies another medical or physical condition, such as endometriosis or uterine fibroids.
Menorrhagia (Heavy Bleeding)
During a normal menstrual cycle, the average woman loses about 1 ounce (30 mL) of blood. Most women change their tampons or pads around 3 - 6 times per day. Menorrhagia is the medical term for significantly heavier periods. Menorrhagia can be caused by a number of factors.
Women often overestimate the amount of blood lost during their periods. Clot formation is fairly common during heavy bleeding and is not a cause for concern. However, women should consult their doctor if any of the following occurs:
- Soaking through at least one pad or tampon every 1 - 2 hours for several hours
- Heavy periods that regularly last 10 or more days
- Bleeding between periods or during pregnancy. Spotting or light bleeding between periods is common in girls just starting menstruation and sometimes during ovulation in young adult women, but it is still a good idea to speak with a doctor. Women who experience any post-menopausal bleeding should definitely contact their doctors.
Menorrhagia is menstrual flow that lasts longer and is heavier than normal. The bleeding occurs at regular intervals (during periods). It usually lasts more than 7 days and women lose an excessive (more than 80 mL) amount of blood. Menorrhagia is often accompanied by dysmenorrhea because passing large clots can cause painful cramping.
Menorrhagia is a type of abnormal uterine bleeding. Other types of abnormal bleeding are:
- Metrorrhagia, also called breakthrough bleeding, refers to bleeding that occurs at irregular intervals and with variable amounts. The bleeding occurs between periods or is unrelated to periods.
- Menometrorrhagia refers to heavy and prolonged bleeding that occurs at irregular intervals. Menemetrorrhagia combines features of menorrhagia and metrorrhagia. The bleeding can occur at the time of menstruation (like menorrhagia) or in between periods (like metrorrhagia).
- Dysfunctional uterine bleeding (DUB) is a general term for abnormal uterine bleeding that usually refers to extra or excessive bleeding caused by hormonal problems, usually lack of ovulation (anovulation). DUB tends to occurs either when girls begin to menstruate or when women approach menopause, but it can occur at any time during a woman's reproductive life.
- Other types of abnormal uterine bleeding include bleeding after sex and bleeding after menopause.
Amenorrhea (Absence of Menstruation)
Amenorrhea is the absence of menstruation. There are two categories: primary amenorrhea and secondary amenorrhea. These terms refer to the time when menstruation stops:
- Primary amenorrhea occurs when a girl does not begin to menstruate by age 16. Girls who show no signs of sexual development (breast development and pubic hair) by age 13 should be evaluated by a doctor. Any girl who does not have her period by age 15 should be evaluated for primary amenorrhea.
- Secondary amenorrhea occurs when periods that were previously regular stop for at least 3 months.
Oligomenorrhea (Light or Infrequent Menstruation)
Oligomenorrhea is a condition in which menstrual cycles are infrequent, greater than 35 days apart. It is very common in early adolescence and does not usually indicate a medical problem.
When girls first menstruate they often do not have regular cycles for several years. Even healthy cycles in adult women can vary by a few days from month to month. Periods may occur every 3 weeks in some women, and every 5 weeks in others. Flow also varies and can be heavy or light. Skipping a period and then having a heavy flow may occur; this is most likely due to missed ovulation rather than a miscarriage.
Premenstrual Syndrome (PMS)
Premenstrual syndrome (PMS) is a set of physical, emotional, and behavioral symptoms that occur during the last week of the luteal phase (a week before menstruation) in most cycles. The symptoms typically do not start until at least day 13 in the cycle, and resolve within 4 days after bleeding begins. Women may begin to have premenstrual syndrome symptoms at any time during their reproductive years, but it usually occurs when they are in their late 20s to early 40s. Once established, the symptoms tend to remain fairly constant until menopause, although they can vary from cycle to cycle.
Many different factors can trigger menstrual disorders, such as hormone imbalances, genetic factors, clotting disorders, and pelvic diseases.
Causes of Dysmenorrhea (Painful Periods)
Primary dysmenorrhea is caused by prostaglandins, hormone-like substances that are produced in the uterus and cause the uterine muscle to contract. Prostaglandins also play a role in the heavy bleeding that causes dysmenorrhea.
Secondary dysmenorrhea can be caused by a number of medical conditions. Common causes of secondary dysmenorrhea include:
- Endometriosis. Endometriosis is a chronic and often progressive disease that develops when the tissue that lines the uterus (endometrium) grows onto other areas, such as the ovaries, bowels, or bladder. It often causes chronic pelvic pain.
Endometriosis is the condition in which the tissue that normally lines the uterus (endometrium) grows on other areas of the body, causing pain and irregular bleeding.
Causes of Menorrhagia (Heavy Bleeding)
There are many possible causes for heavy bleeding:
- Hormonal Imbalances. Imbalances in estrogen and progesterone levels can cause heavy bleeding. Hormonal imbalances are common around the time of menarche and menopause.
- Ovulation Problems. If ovulation does not occur (anovulation), the body stops producing progesterone, which can cause heavy bleeding.
- Uterine Fibroids. Uterine fibroids are a very common cause of heavy and prolonged bleeding.
- Uterine Polyps. Uterine polyps (small benign growths) and other structural problems or other abnormalities in the uterus may cause bleeding.
- Endometriosis and Adenomyosis. Endometriosis, a condition in which the cells that line the uterus grow outside of the uterus in other areas, such as the ovaries, can cause heavy bleeding. Adenomyosis, a related condition where endometrial tissue develops within the muscle layers of the uterus, can also cause heavy bleeding and menstrual pain.
Medications and Contraceptives. Certain drugs, including anticoagulants and anti-inflammatory medications, can cause heavy bleeding. Problems linked to some birth control methods, such as birth control pills or intrauterine devices (IUDs) can cause bleeding.
Bleeding Disorders. Bleeding disorders that stop blood from clotting can cause heavy menstrual bleeding. Most of these disorders have a genetic basis. Von Willebrand disease is the most common of these bleeding disorders.
Cancer. Rarely, uterine, ovarian, and cervical cancer can cause excessive bleeding.
Infection. Infection of the uterus or cervix can cause bleeding.
Pregnancy or Miscarriage.
Other Medical Conditions. Systemic lupus erythematosus, diabetes, pelvic inflammatory disorder, cirrhosis, and thyroid disorders can cause heavy bleeding.
Fibroid tumors may not need to be removed if they are not causing pain, bleeding excessively, or growing rapidly.
Causes of Amenorrhea and Oligomenorrhea (Absent or Light Periods)
Normal causes of skipped or irregular periods include pregnancy, breastfeeding, hormonal contraception, and perimenopause. Skipped periods are also common during adolescence, when it may take a while before ovulation occurs regularly. Consistently absent periods may be due to the following factors:
Delayed Puberty. A common cause of primary amenorrhea (absence of periods) is delayed puberty due to some genetic factor that delays physical development. Failure of ovarian development is the most common cause of primary amenorrhea.
Hormonal Changes and Puberty. Oligomenorrhea (light or infrequent menstruation) is commonly experienced by girls who are just beginning to have their periods.
Weight Loss and Eating Disorders. Eating disorders are a common cause of amenorrhea in adolescent girls. Extreme weight loss and reduced fat stores lead to hormonal changes that include low thyroid levels (hypothyroidism) and elevated stress hormone levels (hypercortisolism). These changes produce a reduction in reproductive hormones.
Polycystic Ovarian Syndrome (PCOS). PCOS is a condition in which the ovaries produce high amounts of androgens (male hormones), particularly testosterone. Amenorrhea or oligomenorrhea is quite common in women who have PCOS.
Endometriosis. Endometriosis, and adenomyosis, can cause severe pelvic pain especially during menstruation. In endometriosis, cells from the tissue that lines the uterus grow in sites outside the uterus. In adenomyosis, these endometrial cells grow within and become attached to the muscular walls of the uterus.
Elevated Prolactin Levels (Hyperprolactinemia). Prolactin is a hormone produced in the pituitary gland that stimulates breast development and milk production in association with pregnancy. High levels of prolactin (hyperprolactinemia) in women who are not pregnant or nursing can reduce gonadotropin hormones and inhibit ovulation, thus causing amenorrhea.
Premature Ovarian Failure (POF). POF is the early depletion of follicles before age 40. In most cases, it leads to premature menopause. POF is a significant cause of infertility.
Structural Problems. In some cases, structural problems or scarring in the uterus may prevent menstrual flow. Inborn genital tract abnormalities may also cause primary amenorrhea.
Stress. Physical and emotional stress may block the release of luteinizing hormone, causing temporary amenorrhea.
. Amenorrhea or oligomenorrhea associated with vigorous activity may be related to stress and weight loss. Female athletes who use anabolic steroids will often have amenorrhea or oligomenorrhea. A syndrome known as the female athlete triad is associated with hormonal changes that occur with the combination of eating disorders
, amenorrhea, and osteopenia (loss of bone density that can lead to osteoporosis) in young women who excessively exercise.
Other Medical Conditions. Epilepsy, thyroid problems, celiac sprue, metabolic syndrome, and Cushing's disease are associated with amenorrhea.
If the ovaries produce too much androgen (hormones such as testosterone) a woman may develop male characteristics. This ovarian imbalance can be caused by tumors in the ovaries or adrenal glands, or polycystic ovarian disease. Virilization may include growth of excess body and facial hair, amenorrhea (loss of menstrual period) and changes in body contour.
Age plays a key role in menstrual disorders. Girls who start menstruating at age 11 or younger are at higher risk for severe pain, longer periods, and longer menstrual cycles. Adolescents may develop amenorrhea before their ovulation cycles become regular.
Women who are approaching menopause (perimenopause) may also skip periods. Occasional episodes of heavy bleeding are also common as women approach menopause.
Other risk factors include:
Weight. Being either excessively overweight or underweight can increase the risk for dysmenorrhea and amenorrhea.
Menstrual Cycles and Flow. Longer and heavier menstrual cycles are definitely associated with painful cramps.
Pregnancy History. Women who have had a higher number of pregnancies are at increased risk for menorrhagia. Women who have never given birth have a higher risk of dysmenorrhea, while women who first gave birth at a young age are at lower risk.
Smoking. Smoking can increase the risk for heavier periods.
Stress. Physical and emotional stress may block the release of luteinizing hormone, causing temporary amenorrhea.
Menorrhagia is the most common cause of anemia (reduction in red blood cells) in premenopausal women. A blood loss of more than 80mL (around three tablespoons) per menstrual cycle can eventually lead to anemia. Most cases of anemia are mild. Nevertheless, even mild anemia can reduce oxygen transport in the blood, causing fatigue and a diminished physical capacity. Moderate-to-severe anemia can cause shortness of breath, rapid heart rate, lightheadedness, headaches, ringing in the ears (tinnitus), irritability, pale skin, restless legs syndrome, and mental confusion. Heart problems can occur in prolonged and severe anemia that is not treated.
Amenorrhea caused by reduced estrogen levels is linked to osteopenia (loss of bone density) and osteoporosis (more severe bone loss that increases fracture risk). Conditions that are associated with low estrogen levels include eating disorders, pituitary tumors, and premature ovarian failure. Because bone growth is at its peak in adolescence and young adulthood, losing bone density at that time is very dangerous, and early diagnosis and treatment is essential for long-term health.
Osteoporosis is a condition characterized by progressive loss of bone density, thinning of bone tissue, and increased vulnerability to fractures. Osteoporosis may result from disease, dietary or hormonal deficiency, or advanced age. Regular weight-bearing exercise and strength training, and calcium and vitamin D supplements, can reduce and even reverse loss of bone density.
Some conditions associated with heavy bleeding, such as ovulation abnormalities, fibroids, or endometriosis, are important contributors to infertility. Many conditions that cause amenorrhea, such as ovulation abnormalities and polycystic ovary syndrome, can also cause infertility. Irregular periods from any cause may make it more difficult to conceive. Sometimes treating the underlying condition can restore fertility. In other cases, specific fertility treatments that use assisted reproductive technologies may be beneficial.
Quality of Life
Menstrual disorders, particularly pain and heavy bleeding, can affect school and work productivity and social activities.
Your medical history can help the doctor determine whether a menstrual problem is caused by another medical condition. For example, non-menstrual conditions that may cause abdominal pain include appendicitis, urinary tract infections, ectopic pregnancy, and irritable bowel syndrome. Endometriosis and uterine fibroids may cause heavy bleeding and pain. Your doctor may ask questions concerning:
Menstrual Diary. A menstrual diary is a helpful way to keep track of changes in menstrual cycles. You should record when your period starts, how long it lasts, and the amount of bleeding and pain that occurs during the course of menstruation.
Pelvic Examination. A pelvic exam is a standard part of diagnosis. A Pap test may be done during this exam.
Blood and Hormonal Tests
Blood tests can help rule out other conditions that cause menstrual disorders. For example, your doctor may test thyroid function to make sure that low thyroid (hypothyroidism) is not present. Blood tests can also check follicle-stimulating hormone, estrogen, and prolactin levels. Patients who have menorrhagia may get tests for bleeding disorders. If patients are losing a lot of blood, they should also get tested for anemia.
Patients who have amenorrhea may need to receive special hormonal tests. The progestational challenge test uses oral or injected progesterone to test for a functional uterine lining (endometrium):
- Bleeding that occurs up to 3 weeks after the progesterone dose suggests that the woman has normal estrogen levels but is not ovulating, particularly if thyroid and prolactin levels are normal. In such cases, the doctor will check for stress, recent weight loss, and any medications. Such results could also suggest polycystic ovaries or stress.
- A failure to bleed could indicate an abnormal uterus that prevents outflow or insufficient estrogen. In such cases, the next step may be to administer estrogen, followed by progestin. If bleeding occurs after that, the cause of amenorrhea is related to low estrogen levels. The doctor will then check for ovarian failure, anorexia, or other causes of low estrogen. If bleeding does not occur, the doctor would check for obstructions that are preventing outflow of menstruation.
Imaging techniques are often used to detect certain conditions that may be causing menstrual disorders. Imaging can help diagnose fibroids, endometriosis, or structural abnormalities of the reproductive organs.
Ultrasound and Sonohysterography. Ultrasound is the standard imaging technique for evaluating the uterus and ovaries, detecting fibroids, ovarian cysts and tumors, and finding obstructions in the urinary tract. It uses sound waves to produce an image of the organs. Ultrasound carries no risk and causes very little discomfort.
Transvaginal sonohysterography uses ultrasound along with saline (salt water) injected into the uterus to enhance the visualization of the uterus.
Other Diagnostic Procedures
Hysteroscopy. Hysteroscopy is a procedure that can detect the presence of fibroids, polyps, or other causes of bleeding. It may miss cases of uterine cancer, however, and is not a substitute for more invasive procedures, such as dilation and curettage (D&C) or endometrial biopsy, if cancer is suspected.
It is done in the office setting and requires no incisions. The procedure uses a slender flexible or rigid tube called a hysteroscope, which is inserted into the vagina and through the cervix to reach the uterus. A fiber-optic light source and a tiny camera in the tube allow the doctor to view the cavity. The uterus is filled with saline or carbon dioxide to inflate the cavity and provide better viewing. This can cause cramping.
Hysteroscopy is non-invasive, but many women find the procedure painful. The use of an anesthetic spray such as lidocaine may help in preventing pain from this procedure. Other complications include excessive fluid absorption, infection, and uterine perforation. Hysteroscopy is also performed as part of surgical procedures.
Laparoscopy. Diagnostic laparoscopy, an invasive surgical procedure, is currently the only definitive method for diagnosing endometriosis, a common cause of dysmenorrhea. It may also be used to treat endometriosis. Laparoscopy normally requires a general anesthetic, although the patient can go home the same day. The procedure involves inflating the abdomen with gas through a small abdominal incision. A fiber optic tube equipped with small camera lenses (the laparoscope) is then inserted. The doctor uses the laparoscope to view the uterus, ovaries, tubes, and peritoneum (lining of the pelvis).
Endometrial Biopsy. When heavy or abnormal bleeding occurs, an endometrial (uterine) biopsy can be performed in the doctor's office. This procedure can help identify abnormal cells, which suggest that cancer may be present. It may also help the doctor decide on the best hormonal treatment to use. The procedure is done without anesthesia, or local anesthetic is injected.
The patient lies on her back with her feet in stirrups. An instrument (speculum) is inserted into the vagina to hold it open and allow the cervix to be viewed.
The cervix is cleaned with an antiseptic liquid and then grasped with an instrument (tenaculum) that holds the uterus steady. A device called a cervical dilator may be needed to stretch the cervical canal if there is tightness (stenosis). A small, hollow plastic tube is then gently passed into the uterine cavity.
Gentle suction removes a sample of the lining. The tissue sample and instruments are removed. A specialist called a pathologist examines the sample under a microscope.
Dilation and Curettage (D&C). Dilation and curettage (D&C) is a more invasive procedure:
- A D&C is usually done in an outpatient setting so that the patient can return home the same day, but it sometimes requires a general anesthetic. It may need to be performed in the operating room to rule out serious conditions or treat some minor ones that may be causing the bleeding.
- The cervix (the neck of the uterus) is dilated (opened).
- The surgeon scrapes the inside lining of the uterus and cervix.
The procedure is used to take samples of the tissue and to relieve heavy bleeding in some instances. D&C can also be effective in scraping off small endometrial polyps, but it is not useful for most fibroids, which tend to be larger and more firmly attached.
Making dietary adjustments starting about 14 days before a period may help some women with certain mild menstrual disorders, such as cramping. The general guidelines for a healthy diet apply to everyone; they include eating plenty of whole grains, fresh fruits and vegetables, and avoiding saturated fats and commercial junk foods.
Limiting salt (sodium) may help reduce bloating. Limiting caffeine, sugar, and alcohol intake may also be beneficial.
Preventing and Treating Anemia
Dietary Forms of Iron. Women who have heavy menstrual bleeding can sometimes become anemic. Eating iron-rich foods can help prevent anemia. Iron found in foods is either in the form of heme or non-heme iron. Heme iron is better absorbed than non-heme iron.
- Foods containing heme iron are the best sources for increasing or maintaining healthy iron levels. Such foods include (in order of iron-richness) clams, oysters, organ meats, beef, pork, poultry, and fish.
- Non-heme iron is less well absorbed. A substantial amount of the iron in meat is non-heme (although meat itself helps absorb non-heme iron). Eggs, dairy products, and iron-containing vegetables have only the non-heme form. Such vegetable products include dried beans and peas, iron-fortified cereals, bread, and pasta products, dark green leafy vegetables (chard, spinach, mustard greens, kale), dried fruits, nuts, and seeds.
Increasing intake of vitamin C rich foods can enhance absorption of non-heme iron.
Iron Supplements. There are two forms of supplemental iron: ferrous and ferric. Ferrous iron is better absorbed and is the preferred form of iron tablets. Ferrous iron is available in three forms: ferrous fumarate, ferrous sulfate, and ferrous gluconate. Depending on the severity of your anemia, as well as your age and weight, your doctor will recommend a dosage of 60 - 200 mg of elemental iron per day. This means taking one iron pill 2 - 3 times each day.
Other Lifestyle Measures
Exercise. Exercise may help reduce menstrual pain.
Sexual Activity. There have been reports that orgasm reduces the severity of menstrual cramps.
Applying Heat. Applying a heating pad to the abdominal area, or soaking in a hot bath, can help relieve the pain of menstrual cramps.
Menstrual Hygiene. Change tampons every 4 - 6 hours. Avoid scented pads and tampons; feminine deodorants can irritate the genital area. Douching is not recommended because it can destroy the natural bacteria normally present in the vagina. Bathing regularly is sufficient.
Acupuncture and Acupressure. Some studies have reported relief from pelvic pain after acupuncture or acupressure, a technique that applies small pins or pressure to specific points on the body. More research is needed.
Yoga and Meditative Techniques. Yoga and meditative techniques that promote relaxation may help relieve menstrual cramps.
Herbs and Supplements. Generally, manufacturers of herbal remedies and dietary supplements do not need approval from the Food and Drug Administration to sell their products. Just like with drugs, herbs and supplements can affect the body's chemistry, and therefore have the potential to produce side effects that may be harmful. There have been a number of reported cases of serious and even lethal side effects from herbal products. Patients should check with their doctor before using any herbal remedies or dietary supplements.
Studies have not generally found herbal or natural remedies to be any more effective than placebos (sugar pills) for reducing menstrual disorders. Natural remedies promoted for menstrual symptoms include:
- Black cohosh (also known as Cimicifuga racemosa or squawroot) contains a plant estrogen and is the most studied herbal remedy for treating menopausal symptoms, including dysmenorrhea, although most studies have indicated it is ineffective. Headaches and gastrointestinal problems are common side effects. It should not be taken for more than 6 months.
- Ginger tea or capsules may help to relieve nausea and bloating.
- Magnesium supplements may be helpful for relieving dysmenorrhea. Some women also report benefit with vitamin B1 (thiamine) supplements.
- Aromatherapy with topically-applied lavender, sage, and rose oils may help ease menstrual cramps, according to some small studies.
- Pycnogenol, an extract from the bark of the French maritime pine tree, may help reduce menstrual pain and discomfort, according to some small studies.
There are a number of different medicines prescribed for menstrual disorders.
Common Pain Relievers for Cramps
Nonsteroidal Anti-inflammatory Drugs (NSAIDs). Nonsteroidal anti-inflammatory drugs (NSAIDs) block prostaglandins, the substances that increase uterine contractions. They are effective painkillers that also help control the inflammatory factors that may be responsible for heavy menstrual bleeding. Aspirin is the most common NSAID, but there are dozens of others available over the counter or by prescription.
Among the most effective NSAIDs for menstrual disorders are ibuprofen (Advil, Motrin, Midol PMS, generic) and naproxen (Aleve, generic), which are both available over-the-counter, and mefenamic acid (Ponstel, generic), which requires a doctor’s prescription. Long-term daily use of any NSAID can increase the risk for gastrointestinal bleeding and ulcers, so it’s best to just use these drugs for a few days during the menstrual cycle.
An ulcer is a crater-like lesion on the skin or mucous membrane caused by an inflammatory, infectious, or malignant condition. To avoid irritating an ulcer a person can try eliminating certain substances from their diet such as caffeine, alcohol, aspirin, and avoid smoking. Patients can take certain medicines to suppress the acid in the stomach causing the erosion of the stomach lining. Endoscopic therapy can be used to stop bleeding from the ulcer.
Acetaminophen. Acetaminophen (Tylenol, generic) is a good alternative to NSAIDs, especially for women with stomach problems or ulcers. Some products (Pamprin, Premsyn, generic) combine acetaminophen with other drugs, such as a diuretic, to reduce bloating. .
Oral contraceptives (OCs), commonly called birth control pills or "the Pill," contain combinations of an estrogen and a progesterone (in a synthetic form called progestin). The estrogen compound used in most combination OCs is estradiol. There are many different progestins, but common types include levonorgestrol, drospirenone, norgestrol, norethindrone, and desogestrel. (Combination contraceptives are also available in other forms, including patches and vaginal rings, but they may increase the risk for menstrual cramping and bleeding.) Natazia, an OC that contains estradiol and the progesterone dienogest, is specifically approved for treatment of heavy bleeding.
OCs are often used to regulate periods in women with menstrual disorders, including menorrhagia (heavy bleeding), dysmenorrhea (severe pain), and amenorrhea (absence of periods). Oral contraceptives are as effective for treating pelvic pain from endometriosis as the more potent gonadotropin releasing hormone agonists. They also protect against ovarian and endometrial cancers.
Standard OCs usually come in a 28-pill pack with 21 days of “active” (hormone) pills and 7 days of “inactive” (placebo) pills. Newer “extended-cycle (also called “continuous-use” or “continuous-dosing”) oral contraceptives aim to reduce -- or even eliminate -- monthly menstrual periods. These OCs contain a combination of estradiol and the progestin levonorgestrel, but they use extending dosing of active pills.
Extended-cycle oral contraceptives include:
Seasonale and Seasonique, which reduce periods to about 3 or 4 times a year
Lybrel, which completely eliminates monthly menstrual periods in many women
Side effects. Common side effects of combination OCs include headache, nausea, bloating, breast tenderness, and bleeding between periods. The estrogen component in combination OCs is usually responsible for these side effects. In general, today’s OCs are much safer than OCs of the past because they contain much lower dosages of estrogen.
However, all OCs can increase the risk for migraine, stroke, heart attack, and blood clots. The risk is highest for women who smoke, who are over age 35, or who have a history of heart disease risk factors (such as high blood pressure or diabetes) or past cardiac events. Women who have certain metabolic disorders, such as polycystic ovary syndrome (PCOS), are also at higher risk for the heart-related complications associated with these pills.
Progestins (synthetic progesterone) are used by women with irregular or skipped periods to restore regular cycles. They also reduce heavy bleeding and menstrual pain, and may protect against uterine and ovarian cancers. Progestin-only contraceptives may be a good option for women who are not candidates for estrogen-containing OCs, such as smokers over the age of 35.
Progestins can be delivered in various forms.
Oral. Short-term treatment of anovulatory bleeding (bleeding caused by lack of ovulation) may involve a 21-day course of an oral progestin on days 5 - 26. Medroxyprogesterone (Provera, generic) is commonly used.
Intrauterine Device (Mirena). An intrauterine device (IUD) that releases progestin can be very beneficial for menstrual disorders, regardless of its contraceptive effects. In the United States, a levonorgestrel-releasing intrauterine system, also called an LNG-IUS, is sold under the brand name Mirena. The LNG-IUS has been proven to reduce heavy bleeding and pain in many women who suffer from menorrhagia and dysmenorrhea. It is the only IUD approved by the FDA to treat heavy menstrual bleeding.
Many doctors recommend the LNG-IUS as a first-line treatment for severe heavy menstrual bleeding, particularly for women who may face hysterectomy (removal of uterus) or conservative surgery such as endometrial ablation (destruction of the endometrial lining). This device is considered a good long-term option, particularly for women who may desire future pregnancies. Research also indicates that women who choose the LNG-IUS are as satisfied with their quality of life as those who choose surgery.
The LNG-IUS remains in place in the uterus and releases the progestin levonorgestrel for up to 5 years. Progestin released by an IUD mainly affects the uterus and cervix, and so it causes fewer widespread side effects than progestin pills do. (However, the other type of IUD -- the Copper T -- may increase bleeding.)
After the LNG-IUS is inserted, heaver periods may occur during the first 3 - 6 months as the lining of the uterus is shed. This shedding may also cause irregular periods and light bleeding (“spotting”) between menstrual cycles. Eventually, the LNG-IUS results in a shorter period, with little or no blood flow. For many women, the LNG-IUS completely stops menstrual periods.
Common side effects include cramping, acne, back pain, breast tenderness, headache, mood changes, and nausea. The LNG-IUS may increase the risk for ovarian cysts, but such cysts usually cause no symptoms and resolve on their own. Women who have a history of pelvic inflammatory disease or who have had a serious pelvic infection should not use the LNG-IUS. Because of the risks associated with pelvic infection, doctors recommend that women who use the LNG-IUS be in a stable monogamous relationship. The LNG-IUS does not protect against sexually transmitted diseases.
Injection (Depo-Provera). Depo-Provera (also called Depo or DMPA) uses the progestin medroxyprogesterone, which is administered by injection once every 3 months. Most women who use Depo-Provera stop menstruating altogether after a year. Depo-Provera may be beneficial for women with heavy bleeding, or pain due to endometriosis. Women who eventually want to have children should be aware that Depo-Provera can cause persistent infertility for up to 22 months after the last injection, although the average is 10 months.
Weight gain can be a problem, particularly in women who are already overweight. Women should not use Depo-Provera if they have a history of liver disease, blood clots, stroke, or cancer of the reproductive organs. Long-term (more than 2 years) use of Depo-Provera can cause loss of bone density. Because of this, Depo-Provera should not be used for longer than 2 years.
Gonadotropin releasing hormone (GnRH) agonists are sometimes used to treat severe menorrhagia. GnRH agonists block the release of the reproductive hormones LH (luteinizing hormone) and FSH (follicular-stimulating hormone). As a result, the ovaries stop ovulating and no longer produce estrogen.
GnRH agonists include the implant goserelin (Zoladex), a monthly injection of leuprolide (Lupron Depot), and the nasal spray nafarelin (Synarel). Such drugs may be used alone or in preparation for procedures used to destroy the uterine lining. They are not generally suitable for long-term use.
Commonly reported side effects, which can be severe in some women, include menopausal-like symptoms. These symptoms include hot flashes, night sweats, changes in the vagina, weight change, and depression. The side effects vary in intensity depending on the GnRH agonist. They may be more intense with leuprolide and persist after the drug has been stopped.
The most important concern is possible osteoporosis from estrogen loss. Women should not take these drugs for more than 6 months. Add-back therapy, which provides doses of estrogen and progestin that are high enough to maintain bone density but are too low to offset the beneficial effects of the GnRH agonist, may be used.
GnRH treatments used alone do not prevent pregnancy. Furthermore, if a woman becomes pregnant during their use, there is some risk for birth defects. Women who are taking GnRH agonists should use non-hormonal birth control methods, such as the diaphragm, cervical cap, or condoms while on the treatments.
Danazol (Danocrine, generic) is a synthetic substance that resembles a male hormone. It suppresses estrogen, and therefore menstruation, and is occasionally used (sometimes in combination with an oral contraceptive) to help prevent heavy bleeding. It is not suitable for long-term use, and due to its masculinizing side effects it is only used in rare cases. GnRH agonists have largely replaced the use of danazol.
Adverse side effects include facial hair, deepening of the voice, weight gain, acne, and reduced breast size. Danazol may also increase the risk for unhealthy cholesterol levels and it may cause birth defects.
Non-Hormonal Drugs (Lysteda)
Tranexamic acid (Lysteda) is a recently approved medication for treating heavy menstrual bleeding. Approved in 2009, it is the first non-hormonal drug for menorrhagia treatment. Tranexamic acid is given as a pill. It is an antifibrinolytic drug that helps blood to clot. The FDA warns that use of this medication by women who take hormonal contraceptives may increase the risk of blood clots, stroke, or heart attacks. This drug should not be taken by women who have a history of blood clots.
Women with heavy menstrual bleeding, painful cramps, or both have surgical options available to them. Most procedures eliminate or significantly affect the possibility for childbearing, however. Hysterectomy removes the entire uterus while endometrial ablation destroys the uterine lining.
For some women, an intrauterine device (IUD) that releases progestin is proving to be a good medical alternative to surgery. The levonorgestrel-releasing intrauterine system, or LNG-IUS (Mirena), is increasingly being used instead of surgery to treat heavy menstrual bleeding. Studies have found the LNG-IUS to work just as well as ablation. Women should be sure to ask their doctors about all medical options before undergoing surgical procedures.
In endometrial ablation, the entire lining of the uterus (the endometrium) is removed or destroyed. For most women, this procedure stops the monthly menstrual flow. In some women, menstrual flow is not stopped but is significantly reduced.
Candidates. Endometrial ablation is not appropriate for women who:
Have gone through menopause
Have recently been pregnant
Would like to have children in the future
Have certain gynecologic conditions such as cancer of the uterus, endometrial hyperplasia, uterine infection, or an endometrium that is too thin
Considerations. Endometrial ablation significantly decreases the likelihood a woman will become pregnant. However, pregnancy can still occur and this procedure increases the risks of complications, including miscarriage. Women who have this procedure must be committed to not becoming pregnant and to using birth control. Sterilization after ablation is another option.
A main concern of endometrial ablation is that it may delay or make it more difficult to diagnose uterine cancer in the future. (Postmenopausal bleeding or irregular vaginal bleeding can be warning signs of uterine cancer.) Women who have endometrial ablation still have a uterus and cervix, and should continue to have regular Pap smears and pelvic exams.
Types of Endometrial Ablation. Endometrial ablation used to be performed in an operating room using electrosurgery with a resectoscope (a hysteroscope with a heated wire loop or roller ball.) Laser ablation was another older procedure. These types of endometrial ablation have largely been replaced by newer types of procedure that do not use a resectoscope.
The newer procedures can be performed either in an operating room or a doctor’s office. They include:
Radiofrequency. The NovaSure system uses a mesh electrode probe that emits electromagnetic energy to destroy the lining.
Heated fluid. In the HydroThermAblator system, a saline solution is inserted into the uterus with a hysteroscope and heated until the lining is destroyed. In the thermal balloon method, a balloon inserted into the uterus with hysteroscope is filled with heated fluid and expanded until it touches and destroys the endometrium.
Freezing. Cryoablation uses liquid nitrogen to freeze the uterine lining.
Microwave. Microwave endometrial ablation applies very low-power microwaves to the uterus.
Before the Procedure. In preparing for the ablation procedure, the doctor will perform an endometrial biopsy to make sure that cancer is not present. If the woman has an intrauterine device (IUD), it must be removed before the procedure. In some cases, hormonal drugs, such as GnRH analogs, may be given a few weeks before ablation to help thin the endometrial lining.
During the Procedure. Endometrial ablation is an outpatient procedure. The doctor usually applies a local anesthetic around the cervix. (The patient also receives medication for pain and to help her relax.) The doctor will dilate the cervix before starting the procedure. Patients may feel some mild cramping or discomfort, but many of the newer types of endometrial procedures can be performed in under 10 minutes.
After the Procedure. Patients may experience menstrual-like cramping for several days and frequent urination during the first 24 hours. The main side effect is watery or bloody discharge that can last for several weeks. This discharge is especially heavy in the first few days following ablation. (Patients need to wear pads, not tampons during this time, and to wait to have sex until the discharge has stopped.) Patients are generally able to return to work or normal activities within a few days after the procedure.
Complications. Complications of endometrial ablation may include perforation of the uterus, injury to the intestine, hemorrhage, or infection. If heated fluid is used in the procedure, it may leak and cause burns. However, in general, the risk of complications is very low.
Nearly all women have reduced menstrual flow after endometrial ablation, and nearly half of women have their periods stop. Some women, however, may continue to have bleeding problems and ultimately decide to have a hysterectomy.
Hysterectomy is the surgical removal of the uterus.
Click the icon to see an illustrated series detailing a hysterectomy.
Heavy bleeding, often from fibroids, and pelvic pain are the reasons for many hysterectomies. However, with newer medical and surgical treatments available, hysterectomies are performed less often than in the past. In its support, hysterectomy, unlike drug treatments and less invasive procedures, cures menorrhagia completely, and most women are satisfied with the procedure. Less invasive hysterectomy procedures are also improving recovery rates and increasing satisfaction afterward.
Still, any woman who is uncertain about a recommendation for a hysterectomy to treat fibroids or heavy bleeding should certainly seek a second opinion.
Nerve Destruction Techniques for Treating Dysmenorrhea
Some evidence suggests that surgically cutting the pain-conducting nerve fibers leading from the uterus diminishes the pain from dysmenorrhea. Two procedures, laparascopic uterine nerve ablation (LUNA) and laparoscopic presacral neurectomy (LPSN), can block such nerves. Some small studies have shown benefits from these procedures, but stronger evidence is needed before they can be recommended for women with severe primary dysmenorrhea or the chronic pelvic pain associated with endometriosis. Many insurance companies consider these procedures experimental and will not pay for them.
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- Last Reviewed on 09/26/2012
- Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.
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