Most women in their reproductive years accept menstruation as a normal part of life, if not exactly their favorite part. Though frequency, duration, and other period-related matters may vary from one girl or woman to the next, the fact that you get one is healthy—and not getting your period (called amenorrhea) may signal that something is amiss.

Amenorrhea is not a disease, but it can be a symptom of other conditions including hormonal, genetic, and structural disorders. Amenorrhea is normal before puberty, during pregnancy, while breastfeeding, and after menopause.

The menstrual cycle is controlled by a complex hormonal system. Each month, hormones are released in a certain order to prepare the uterus and the rest of the body for pregnancy. If everything is operating correctly and there is no pregnancy, the uterus sheds its lining, leading to menstruation. But if some aspect of the hormonal system isn’t working correctly, the result can be amenorrhea. In fact, hormonal issues are the most common reason for it.

The condition is broken into two categories. Primary amenorrhea, which can be caused by congenital differences in the development of reproductive organs, is the failure to have your first period by age 16 (when there is already breast development and other changes of puberty, or secondary sexual characteristics). If there are no secondary sexual characteristics by age 14, you should seek medical care. Secondary amenorrhea is when women experience an absence of their period for more than three cycles—after having had regular periods. Secondary amenorrhea is much more common than primary amenorrhea but, if not related to pregnancy or other circumstances, such as the use of particular types of birth control that prevent periods, is rare, affecting 3 to 4 percent of women.  

Amenorrhea often resolves when the underlying condition is treated. At Yale Medicine, our obstetrician-gynecologists are experienced at diagnosing and treating primary and secondary amenorrhea.

Physicians at Yale Medicine are well-equipped to diagnose any of these conditions, as well as provide comprehensive care for patients diagnosed with amenorrhea. “We offer care throughout the lifespan, from pediatric and adolescent gynecology through menopause,” says Alla Vash-Margita, MD, chief of Yale Medicine Pediatric & Adolescent Gynecology.

The absence of menstrual periods is the most common symptom of amenorrhea. Depending on the cause, you may experience these symptoms as well: 

• Excess body hair (hirsutism)
• Hair loss
• Headache
• Lack of breast development
• Milky discharge from the breasts
• Vision changes
• Failure to ovulate

In addition to genetic conditions, anything that can disrupt the normal functioning of the hypothalamic or pituitary gland can lead to amenorrhea.

Specific risk factors for amenorrhea include the following: 

• Family history of amenorrhea or early menopause
• Excessive exercise
• Obesity
• Eating disorders
• Genetics, including having a change to the FMRI gene 

Amenorrhea can happen naturally in a woman’s life, such as when she is pregnant, breastfeeding, or after menopause. Outside of those circumstances, primary or secondary amenorrhea can be caused by a variety of the below factors: 

• Polycystic ovary syndrome (PCOS): This syndrome is a collection of symptoms associated with certain hormone imbalances.
• Hypothalamic amenorrhea: This occurs when the hypothalamus (a gland in the brain that releases hormones and regulates body temperature, among other functions) slows or stops releasing a hormone (gonadotropin-releasing hormone or GnRH) that starts the menstrual cycle.
• Hyperprolactinemia: This condition means you have higher-than-normal levels of the hormone prolactin in your blood, which can cause menstrual irregularities.
• Ovarian failure: Also known as primary ovarian insufficiency, this is the loss of normal function of your ovaries before age 40.    

In rare cases, primary amenorrhea can be caused by physical problems, such as an absent uterus. Occasionally, menses do occur but there is an obstruction in a form of transverse vaginal septum—when a wall of tissue runs horizontally across the vagina—leading to concealed menstruation. 

A variety of factors can lead to secondary amenorrhea: 

• Medications: Certain methods of birth control, antidepressants, and blood pressure medications work by increasing the level of a hormone that prevents ovulation, thereby preventing menstruation. Some chemotherapy and radiation treatments may also cause amenorrhea.
• Scar tissue: A buildup of scar tissue in the lining of the uterus can prevent it from shedding during menstruation. Such scarring might occur after dilation and curettage (D&C), in which tissue is removed to treat heavy menstrual bleeding, or to clear the lining after a miscarriage, C-section, or to treat uterine fibroids.
• Thyroid problems: The thyroid gland produces hormones that control metabolism and affect puberty and menstruation. A gland that is overactive (hyperthyroidism) or underactive (hypothyroidism) can cause amenorrhea.
• Pituitary tumors: The pituitary gland regulates production of hormones that affect metabolism, the reproductive cycle, and other functions. Tumors on this gland are not usually cancerous, but they can interfere with menstruation. 

If you are sexually active and have not gotten your period, your doctor will likely order a pregnancy test and also perform a pelvic exam.

If you are older than 16 and have never had a period, your doctor will go through your medical history and perform a pelvic exam to see if you are experiencing any signs of puberty or to see if there are any anatomic problems.

Next, your doctor will likely order the following tests to determine the cause of your amenorrhea: 

• Imaging tests: Magnetic resonance imaging (MRI), computed tomography (CT), and ultrasounds of the abdomen and pelvis can be used to detect a tumor in the ovaries or adrenal glands. You doctor will also be able to see birth defects that could block menstrual flow.
• Blood tests: These measure levels of various hormones including prolactin, thyroid, and follicle-stimulating hormone. Levels that are too high or too low in any of these can disrupt the menstrual cycle.
• Hysteroscopy: In this procedure, a thin, lighted camera is passed through the vagina and cervix to allow your doctor to examine the inside of your uterus
• Genetic screening: Changes in the FMR1 gene can cause the ovaries to stop functioning properly and lead to amenorrhea. Screening also looks for a condition called Turner’s syndrome, in which there is partial or complete absence of one X chromosome. This can cause primary amenorrhea.
• Chromosome evaluation: Also known as a karyotype, this test involves counting and studying chromosomes to identify missing, rearranged, or extra cells, which can help determine the abnormality causing amenorrhea.

Treatment for amenorrhea typically focuses on addressing the underlying disorder that is causing it, through the use of behavioral modification, medications, surgeries, or a combination of both. For example, surgery may be recommended to correct a physical abnormality that is blocking the flow of menstrual blood.  

Primary amenorrhea caused by a genetic condition called gonadal dysgenesis (Swyer syndrome)—in which the gonads do not develop normally, increasing the risk of gonadal cancer—typically requires surgical removal of the gonads to prevent cancer. In some genetic disorders, including Turner syndrome, patients will need lifelong hormonal replacement.

Depending on your age and the results of physical exam and various tests, a doctor may recommend “watchful waiting” for a girl with primary amenorrhea. If an ovary function test reveals low levels of follicle-stimulating hormone (FSH) or lutenizing hormone (LH), menstruation may be delayed. And if there is a family history of this, checking in three to six months may be all the doctor recommends.

Common medical treatments for secondary amenorrhea include:

• Birth control pills or other types of hormonal medications may reset the menstrual cycle.
• In patients with secondary amenorrhea due to PCOS who desire pregnancy, medications such as clomiphene citrate, may be prescribed to help trigger ovulation.
• Estrogen replacement therapy may help balance hormone levels and restart the menstrual cycle in women with primary ovarian insufficiency. 

At Yale Medicine, our gynecologists are skilled at treating a host of medical issues that affect the menstrual cycles of adolescents and women. Our physician-scientists are involved in research geared toward better understanding disease processes that affect a woman’s reproductive health.

“At Yale, multiple specialties work closely together. This includes urogynecology, pediatric surgery, pediatric urology and pediatric and adult endocrinology,” says Dr. Vash-Margita. “We also offer many resources, including nutritional advice, psychotherapy, behavioral health, and social work, depending on a patient’s needs.”