Amenorrhea - Absent Menstruation


Amenorrhea is a medical term that means the absence of menstruation.  Amenorrhea is considered a symptom and not a disease because it usually results from another condition.  There are numerous reasons for a missed period for females that are not pregnant, lactating, or in menopause.  Most of the conditions that cause amenorrhea respond to treatment.


The menstrual cycle is a regular process that is regulated by hormones.  The average menstrual cycle lasts around 28 days, but it varies among individuals and may be either longer or shorter.  Each month the uterine lining thickens as it builds up extra blood and tissue in preparation for a potential fertilized egg.  An egg that is fertilized by a sperm cell may implant itself in the nourishing uterine lining and develop into a baby.  An unfertilized egg or a fertilized egg that does not implant in the uterus passes through the reproductive system.  During menstruation prostaglandins, a hormone-like substance, cause the uterus to contract.  The uterine lining sheds and the blood leaves the body through the vagina.


Amenorrhea means the absence of menstrual periods.  Amenorrhea is a symptom of an underlying condition and is not considered a disease.  There are numerous conditions that may cause amenorrhea.  Amenorrhea is classified as primary or secondary. 


Primary amenorrhea refers to a first period that has not occurred in a female by the age of 16.  Most girls begin menstruating around the age of 12.  There are numerous causes of primary amenorrhea.  Some of the most common causes include chromosomal abnormalities, pituitary disease or tumor, vaginal obstruction, being born without all of the female reproductive organs, and problems with the hypothalamus in the brain.  The hypothalamus is a structure that helps regulate menstruation.  Anorexia and excessive exercise or stress can disrupt the normal function of the hypothalamus.


Secondary amenorrhea occurs much more frequently than primary amenorrhea.  Secondary amenorrhea refers to absent periods in females that have already started menstruating and that are not pregnant, breast feeding, or in menopause.  There are numerous causes of secondary amenorrhea. Common causes include birth control pill, contraceptive shots, contraceptive implants, stress, certain medications, hormonal imbalance, polycystic ovary disease, low body weight or body fat, excessive exercise, thyroid problems, pituitary tumor, uterine scar tissue, and premature menopause.


The primary symptom of amenorrhea is no menstrual period.  Primary amenorrhea is characterized by no first menstrual period by the age of 16.  For females that have menstruated, secondary amenorrhea is characterized in as no periods for six months or longer.  Females with secondary amenorrhea may experience other symptoms that are associated with the underlying cause of amenorrhea.


You should contact your doctor if you are over 16 years old and have never had a period or if you have menstruated but have missed two or more periods in a row.  Your doctor will review your medical history, conduct a pelvic examination, and take some tests to determine the underlying cause of your amenorrhea.  Blood, urine, or pregnancy testing may be conducted.  Your hormones may be tested.  In some cases, imaging tests may be used.

A magnetic resonance imaging (MRI) scan or computed tomography (CT) may be done of your head if your doctor suspects that you may have a pituitary tumor.  A pelvic ultrasound, laparoscopy, or hysteroscopy may be used to reveal structural abnormalities in your reproductive organs.  An ultrasound creates images by using sound waves.  A technician or your doctor will simply place a small conduction device on your skin.  A laparoscopy is a surgical procedure that allows your doctor to view your pelvic cavity.  It involves inserting a thin tube with a lighting device through a small incision in you abdomen.  A laparoscopy is an outpatient test that uses general anesthesia.  A hysteroscopy uses a viewing instrument that is inserted through your vagina and cervix to examine the inside of the uterus.


The type of treatment that you receive depends on the cause of your amenorrhea.  Your doctor may recommend lifestyle changes, such as attaining and maintaining a healthy weight, stress reduction, and an appropriate amount of exercise.  Polycystic ovary syndrome or athletic amenorrhea may be treated with oral contraceptives.  Thyroid or pituitary disorders may be corrected with medications or surgery.  Most of the underlying conditions that cause amenorrhea are treatable.


You can help prevent amenorrhea by reducing the risk factors that you can control.  It is helpful to attain and maintain a healthy weight to exercise, but avoid excessive exercise.  Stress reduction techniques and positive support from positive resources, such as friends, family, co-workers, or counselors can help.  Keep a record of your menstrual cycles and note any symptoms that bother you.  Bring your record to your doctor’s appointment.

Am I at Risk

Young females who have not experienced their first period by the average age of 12 may be at risk for amenorrhea.  Females that have menstruated and exercise excessively and use hormone supplements or have low body fat, low body weight, or obesity have an increased risk of amenorrhea.