Author: Laurie Barclay, MD
CME Author: Désirée Lie, MD, MSEd
Release Date: November 7, 2006
November 7, 2006 — Evaluation of the menstrual cycle is a viable tool to assess healthy development of teen girls’ menstrual patterns, according to new guidelines published by the American Academy of Pediatrics (AAP) in the November issue of Pediatrics.
“Young patients and their parents often are unsure about what represents normal menstrual patterns, and clinicians also may be unsure about normal ranges for menstrual cycle length and amount and duration of flow through adolescence,” write Jonathan D. Klein, MD, and colleagues from the AAP Committee on Adolescence and the American College of Obstetricians and Gynecologists (ACOG) Committee on Adolescent Health Care.
“It is important to be able to educate young patients and their parents regarding what to expect of a first period and about the range for normal cycle length of subsequent menses,” the authors point out. “It is equally important for clinicians to have an understanding of bleeding patterns in girls and adolescents, the ability to differentiate between normal and abnormal menstruation, and the skill to know how to evaluate young patients’ conditions appropriately.”
The committee recommends using the menstrual cycle as “an additional vital sign” to help evaluate normal development and exclude pathological conditions.
Characteristics of normal menstrual cycles in young women are median age at menarche of 12.43 years; mean cycle interval of 32.2 days in the first gynecologic year; typical menstrual cycle interval of 21 to 45 days; menstrual flow length of ≤ 7 days; and menstrual product use of 3 to 6 pads or tampons per day.
Causes of menstrual irregularity may include pregnancy; endocrine causes such as poorly controlled diabetes mellitus, polycystic ovary syndrome (PCOS), Cushing disease, thyroid dysfunction, premature ovarian failure, or late-onset congenital adrenal hyperplasia; acquired conditions such as stress-related hypothalamic dysfunction, medication use, exercise-induced amenorrhea, or eating disorders including anorexia and bulimia; and tumors including ovarian or adrenal tumors and prolactinomas.
The guidelines recommend that once menstruation begins, the menstrual cycle should be evaluated along with an assessment of other vital signs, thus emphasizing the important role of menstrual patterns in reflecting overall health status. This should include asking at every visit for the first date of the patient’s last menstrual period.
Other useful measures may include asking the patient to begin to chart her menses, especially if the bleeding history is vague or thought to be inaccurate. Confirming normal internal and external genital anatomy with a pelvic examination or ultrasonography can rule out significant abnormalities.
Both the AAP and ACOG recommend preventive health visits during adolescence to facilitate communication, and to establish an environment in which a patient can take responsibility for her own reproductive health while being reassured that her concerns will be addressed in a confidential setting. These visits can also provide guidance to young women and their parents concerning normal adolescent physical development.
“Young females should understand that menstruation is a normal part of development and should be instructed on use of feminine products and on what is considered normal menstrual flow,” the authors write. “Ideally, both parents and clinicians can participate in this educational process…. Girls who have been educated about early menstrual patterns will experience less anxiety as development progresses.”
Menstrual periods that may require evaluation are those that have not started within 3 years of thelarche; have not started by 13 years of age in the absence of signs of pubertal development; have not started by 14 years of age accompanied by signs of hirsutism; have not started by 14 years of age with a history or examination suggestive of excessive exercise or eating disorder; have not started by 14 years of age with concerns about genital outflow tract obstruction or anomaly; have not started by 15 years of age; are regular, occurring monthly, and then become markedly irregular; occur more frequently than every 21 days or less frequently than every 45 days; occur 90 days apart even for a single cycle; last for 7 days; or require frequent pad or tampon changes (soaking more than 1 every 1-2 hours).
“Clinicians who are confident in their understanding of early menstrual bleeding patterns may convey information to their patients more frequently and with less prompting; girls who have been educated about menarche and early menstrual patterns will experience less anxiety when they occur,” the authors conclude. “By including an evaluation of the menstrual cycle as an additional vital sign, clinicians reinforce its importance in assessing overall health status for both patients and parents. Just as abnormal blood pressure, heart rate, or respiratory rate may be key to the diagnosis of potentially serious health conditions, identification of abnormal menstrual patterns through adolescence may permit early identification of potential health concerns for adulthood.”
Learning Objectives for This Educational Activity
Upon completion of this activity, participants will be able to:
• Describe normal patterns of menstruation in adolescents.
• List menstrual conditions requiring further evaluation in adolescents.
According to the authors of the current study, knowledge of normal patterns of menstruation in adolescents is important for patient education and for identifying deviations from normal to guide clinical evaluation. Until the mid-1950s menarche had occurred at an increasingly younger age, but there has been no decline in the age of menarche in the past 40 to 50 years. According to the authors, age at menarche varies internationally, especially in less developed countries, and 2 large studies have confirmed that higher body mass index is associated with earlier onset of puberty. Age of menarche can also be associated with other factors such as environment, poverty, nutrition, and access to care.
This position statement of the AAP and ACOG committees on adolescent health care describes the use of the menstrual cycle as a vital sign in the care of adolescent women. Both organizations recommend that adolescent women receive routine health visits and take responsibility for their own reproductive health.
• In young women, the median age of menarche is 12.43 years, the mean cycle interval is 32.2 days in the first gynecologic year, menstrual cycle duration is typically 21 to 45 days, menstrual flow length is less than 7 days, and menstrual product use is 3 to 6 pads daily.
• 10% of women menstruate at 11.1 years, 90% by 13.8 years, and 98% by 15.0 years.
• Age of menstruation for black women is earlier (12.05 years) than for Hispanic females (12.25 years) and non-Hispanic white females (12.55 years).
• Menarche typically occurs 2 to 3 years after thelarche at Tanner stage IV breast development and correlates with age of onset of puberty and breast development.
• During the early years of menarche, cycles may be long because of anovulation but 90% of cycles will be within the range of 21 to 45 days.
• When age at menarche is younger than 12 years, 50% of cycles are ovulatory.
• When age at menarche is older, it may take 8 to 10 years for the adolescent to become fully ovulatory.
• By the third year after menarche, 60% to 80% of menstrual cycles are 21 to 45 days in duration as is typical of adults.
• Normal cycle length is established around the sixth gynecologic year at a chronological age of approximately 19 years.
• Primary amenorrhea has been defined as no menarche by 16 years.
• Secondary amenorrhea is defined as absence of menses for 6 months but since the 95th percentile for cycle length is 90 days, the guidelines advise evaluation after 90 days of amenorrhea.
• Irregular menses may be caused by pregnancy, endocrine disorders, PCOS, hyperprolactinemia, adrenal and ovarian tumors, drug effects, stress, significant weight loss, or substantial change in eating or sleep habits.
• Mean blood loss per menstrual period is 30 mL and chronic blood loss of more than 80 mL is associated with anemia.
• Most adolescent women report changing pads 3 to 6 times daily; flow requiring a change of pad every 1 to 2 hours is considered excessive.
• Acute menorrhagia is most commonly associated with anovulation.
• The most common hematologic problem causing acute menorrhagia is von Willebrand disease; other conditions such as hepatic failure and malignancy are less common. In the general population, the prevalence of von Willebrand disease is 1%, but as many as 1 in 6 girls presenting to the emergency department with acute menorrhagia may have von Willebrand disease.
• Menstrual conditions that may require evaluation include the following:
o No menses within 3 years of thelarche.
o No menses by 13 years with no pubertal development.
o No menses by age 14 years with hirsutism.
o No menses by 14 years with excessive exercise or weight loss.
o No menses by 14 years with suggestion of genital tract obstruction.
o No menses by 15 years.
o Change from regular to irregular menses.
o Menses more frequently than every 21 days or less frequently than every 45 days.
o Menses 90 or more days apart.
o Menses lasting more than 7 days.
o Pad changes more than once very 1 to 2 hours.
Pearls for Practice
• The median age of menarche is 12.43 years, mean menstrual cycle duration is 21 to 45 days, mean cycle interval is 32.2 days in the first gynecologic year, menstrual flow duration is less than 7 days, and menstrual product use is 3 to 6 pads daily.
• Investigation of menses is recommended for menorrhagia, amenorrhea, and irregular menses in adolescent women with previously regular menses.