What is amenorrhea?

Amenorrhea is the absence or abnormal cessation of menses. It is when menstruation is absent during the reproductive years (between puberty and menopause). It is a normal feature before puberty, during pregnancy, breastfeeding and after menopause in females.
Diagnosing amenorrhea is a matter of first determining whether pregnancy is the cause. In the absence of pregnancy, the challenge is to determine the exact cause of absent menses.

The normal menstrual cycle occurs because of changing levels of hormones produced and secreted by the ovaries. The ovaries respond to hormonal signals from the pituitary gland located at the base of the brain, which, in turn, is controlled by hormones produced in the hypothalamus of the brain.
Disorders that affect any component of this regulatory cycle can lead to amenorrhea. The menstrual cycle can be influenced by many internal factors such as temporary changes in hormonal levels, stress, and illness, as well as external or environmental factors.

Amenorrhea is often a sign of another health problem rather than a disease itself. Missing one menstrual period is hardly a sign of a chronic problem or an underlying medical condition, but amenorrhea of longer duration may signal the presence of a disease or chronic condition.
Because it is associated with health conditions that are also linked to infertility, understanding amenorrhea is pertinent.


1. Primary amenorrhea:

It is the failure of menses to occur by age 14 with the absence of secondary sexual characteristics or by age 16 with the presence of secondary sexual characteristics.

2. Secondary amenorrhea

It is defined as the abnormal cessation of menses for a period of 3 consecutive months in a female with regular menses or a period of 6 months in a female with irregular menses. This is normal during pregnancy or while breastfeeding, but it may also mean that there is a problem.

How does amenorrhea occur?

Normal menstrual cycle depends on an intact hypothalamo-pituitory system stimulating the ovaries to produce estrogen and progesterone, and a womb that will respond to both hormones, as well as an open vagina for the passage of blood.  Both primary and secondary amenorrhea can thus result from abnormalities in any of the components linked with the occurrence of menses.

Causes of amenorrhea

The cause of amenorrhea may be physiological or pathological.

Physiological amenorrhea: It is seen before puberty, during pregnancy, breastfeeding and menopause. Pregnancy is the commonest cause of amenorrhea and must be considered in all patients.

Pathological amenorrhea: may be primary or secondary.

1. Primary amenorrhea:

typically results from genetic or anatomical changes in young females.

Genetic or inborn conditions: here, some or all of the normal internal female organs either fail to form normally during fetal development or fail to function properly. 

Primary amenorrhea
  • Turner syndrome: the female lacks all or part of the two X chromosomes normally present in females.
  • Androgen insensitivity syndrome: individuals have male chromosomes but do not develop the external characteristics of males due to lack of response to testosterone and its effect. There is fully female body appearance with breast development and a short vagina
  • Müllerian defects: is a malformation of the reproductive organs. The womb and fallopian tubes do not form as they should.
  • Mayer-Rokitansky-Kuster-Hauser (MRKH) syndrome, the ovaries, breasts, and clitoris form correctly, but there is no vaginal opening, and the cervix and uterus may not be properly formed. In this case, reproductive development will not follow the normal pattern, and menstruation may not be possible.
  • Imperforate hymen: the hymen has no opening.
  • Congenital adrenal hyperplasia

Disorders of the hypothalamus, pituitary gland, ovaries and womb:

  • Primary ovarian insufficiency (premature ovarian failure or premature menopause): characterized by oligomenorrhea/amenorrhea, estrogen deficiency, and its associated symptoms such as hot flashes, vaginal dryness, dyspareunia, and insomnia. 
  • Kallman’s syndrome: a condition characterized by delayed or absent puberty and an impaired sense of smell.
  • Polycystic ovarian syndrome (PCOS):  causes hormonal imbalance in females.
  • Prolactinomas (rare in primary amenorrhea)

2. Secondary amenorrhea

Secondary Amenorrhea

Menstruation may stop for a number of reasons. These include:

The most common causes are

  • Malfunction of the hypothalamus
  • Polycystic ovary syndrome
  • Primary ovarian insufficiency or premature ovarian failure
  • Malfunction of the pituitary gland or the thyroid gland
  • Use of certain drugs, such as birth control pills (oral contraceptives), antidepressants, or antipsychotic drugs.

The hypothalamus may malfunction for various reasons:

  • Stress or stringent exercise (particularly females who participate in sports that involve maintaining a low body weight)
  • Poor eating habit or nutrition (as may occur in females who have an eating disorder or who have lost a significant amount of weight)
  • Mental disorders such as depression 
  • Radiotherapy

The pituitary gland may malfunction because

  • It is damaged.
  • High prolactin levels.

Oral contraceptives (sometimes), antidepressants, antipsychotic drugs, or certain other drugs can cause increase in prolactin levels, as can pituitary tumours and some other disorders.

The thyroid gland may cause amenorrhea if it is under-functioning ( hypothyroidism) or over-functioning ( hyperthyroidism).

Less common causes of secondary amenorrhea include chronic illness, some autoimmune diseases, cancer, HIV infection, radiotherapy, head injuries, a hydatidiform mole (overgrowth of tissue from the placenta), Cushing syndrome, and malfunction of the adrenal glands. Scarring of the womb (usually due to an infection or DIC), polyps, and fibroids can also cause secondary amenorrhea. 

Fragile X syndrome, a genetic disorder, may cause menses to stop early (premature menopause).

Symptoms of amenorrhea

The main symptom is a lack of menses. However, depending on the cause, other symptoms may occur. These include:

  • Delayed puberty
  • Headache.
  • Acne.
  • Milky nipple discharge that occurs spontaneously.
  • Hair loss.
  • Problems with vision.
  • In those with primary amenorrhea, there may be a lack of breast development.
  • Development of male characteristics, such as excess body hair, a deepened voice, and increased muscle size.
  • Altered sense of smell (which may be a symptom of Kallman’s syndrome)
  • A significant change in weight.

Anyone who experiences these symptoms should seek medical advice.

Who is at risk for amenorrhea?

Risk factors for amenorrhea include:

  • A family history of amenorrhea or early menopause.
  • Genetic or chromosomal condition that affects your menstrual cycle.
  • Obesity or being underweight.
  • Disorders of eating.
  • intensive exercising.
  • Poor nutrition.
  • Stress.
  • Severe illness.

1. Infertility. A female that does not ovulate and have menses cannot get pregnant.

What are the complications?

2. Osteopenia/osteoporosis (weakening of the bones) is a complication of low estrogen levels, which may occur with prolonged amenorrhea.

How is it diagnosed?

Because of the multiple causes of amenorrhea, it may take time to find the exact cause.

The doctor will first take a medical history and a physical and pelvic exam will be done. If the female is sexually active, they might first order a pregnancy test to rule out pregnancy as a cause.

It may take several kinds of tests to find out the exact cause of the amenorrhea. The doctor may use one or more of the following:

Blood tests. These measure the levels of certain hormones in the blood, including follicle-stimulating hormone (FSH), thyroid-stimulating hormone, prolactin, and male hormones. Too much or too little of these hormones can interfere with the menstrual cycle.

Imaging tests. These tests can show abnormalities of the reproductive organs or the location of tumors. The tests include ultrasound, computerized tomography (CT), and magnetic resonance imaging (MRI).

Hormone challenge test. Your doctor will give you a hormonal medication that should cause menstrual bleeding when you stop taking it. If you don’t, this can mean that a lack of estrogen is behind your amenorrhea.

Hysteroscopy.  A small lighted camera is put through the vagina and cervix to view the womb.

Genetic screening. Looks for genetic changes that can stop the ovaries from working, and for X chromosomes that are partly or completely missing (Turner’s syndrome).

Chromosome tests (karyotype).  Identifies missing, extra, or rearranged cells in the chromosomes to help pinpoint abnormalities that can cause amenorrhea.

How is it treated?

treatment of amenorrhea

Treatment will depend on the cause.

1. Primary amenorrhea

Treatment for primary amenorrhea may start with watchful waiting, depending on the person’s age and the result of the ovary function test. If there is a family history of late menstruation, periods may start in time. If there are genetic or physical problems that involve the reproductive organs, surgery may be necessary. This will not guarantee, however, that normal menstrual cycles will occur.

2. Secondary amenorrhea

This will depend on the underlying cause.

a. Lifestyle factors: If the person has been exercising excessively, a change of exercise plan or diet may help to stabilize the monthly cycle.

b. Stress: If emotional or mental stress is a problem, counseling may help.

c. Excessive weight loss: This can happen for different reasons. The person may need a professionally supervised weight gain regime. If an eating disorder is a possibility, treatment may include a weight-gain regime and counseling sessions with a psychiatrist and a nutritionist or dietitian. Some health conditions can cause weight loss. A doctor may test for these and offer treatment as appropriate.

d. Hypothyroidism: If menstruation stops because of an underfunctioning thyroid, the doctor may prescribe treatment with thyroxine, a thyroid hormone.

e. Polycystic ovarian syndrome (PCOS): The doctor will suggest appropriate treatment. If PCOS has led to excess weight, they may recommend a weight-loss diet.

f. Premature ovary failure: Hormone replacement therapy (HRT) may cause menstruation to return.

g. Menopause: Menopause starts around the age of 50 years, but sometimes it can start as early as 40 years (premature menopause). Family history can affect this. If menopause starts early, there is a higher risk of osteoporosis. The person may need treatment to prevent this complication.

Can amenorrhea be prevented?

Amenorrhea is a symptom and not a disease in itself. Therefore, amenorrhea can be prevented only to the extent that the exact cause can be prevented. For example, amenorrhea that results from genetic or inborn conditions cannot be prevented. On the other hand, amenorrhea that results from self-imposed strict dieting or rigorous exercise is typically preventable.

E. Ayala, PharmD in view, member YALI Network, Executive member at Impact Africa Initiative, member at LEAD (Living Everyday Above Depression) and member Wrighters Community.

F.O. Adagbonyin, MB.BS in view, certified content creator at Medblog180 and MedicWord, licensed google writer and contributing writer at WikiMedia Foundation.

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