Menstruation in Girls and Adolescents: Using the Menstrual Cycle ...

CLINICAL REPORT
Menstruation in Girls and
Guidance for the Clinician in Rendering
Pediatric Care
Adolescents: Using the Menstrual
Cycle as a Vital Sign
AMERICAN ACADEMY OF PEDIATRICS
Committee on Adolescence
AMERICAN COLLEGE OF OBSTETRICIANS AND GYNECOLOGISTS
Committee on Adolescent Health Care
ABSTRACT
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. 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 subse-
quent menses. 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. Using the menstrual cycle as an additional vital
sign adds a powerful tool to the assessment of normal development and the
exclusion of pathological conditions.
INTRODUCTION
Young patients and their parents frequently have difficulty assessing what consti-
tutes normal menstrual cycles or patterns of bleeding. Girls may be unfamiliar with
what is normal and may not inform their parents about menstrual irregularities or
www.pediatrics.org/cgi/doi/10.1542/
missed menses. Additionally, girls often are reluctant to discuss this very private
peds.2006-2481
topic with a parent, although they may confide in another trusted adult. Some girls
doi:10.1542/peds.2006-2481
will seek medical attention for cycle variations that actually fall within the normal
All clinical reports from the American
range. Others are unaware that their bleeding patterns are abnormal and may be
Academy of Pediatrics automatically
attributable to significant underlying medical issues with the potential for long-
expire 5 years after publication unless
reaffirmed, revised, or retired at or
term health consequences.
before that time.
Clinicians also may be unsure about normal ranges for menstrual cycle length
The guidance in this report does not
and for amount and duration of flow through adolescence. Clinicians who are
indicate an exclusive course of treatment
or serve as a standard of medical care.
confident in their understanding of early menstrual bleeding patterns may convey
Variations, taking into account individual
information to their patients more frequently and with less prompting; girls who
circumstances, may be appropriate.
have been educated about menarche and early menstrual patterns will experience
Key Words
less anxiety when they occur.1 By including an evaluation of the menstrual cycle
menarche, menstruation, adolescent
as an additional vital sign, clinicians reinforce its importance in assessing overall
Abbreviation
PCOS—polycystic ovary syndrome
health status for both patients and parents. Just as abnormal blood pressure, heart
PEDIATRICS (ISSN Numbers: Print, 0031-4005;
rate, or respiratory rate may be key to the diagnosis of potentially serious health
Online, 1098-4275). Copyright © 2006 by the
conditions, identification of abnormal menstrual patterns through adolescence
American Academy of Pediatrics and American
College of Obstetricians and Gynecologists
may permit early identification of potential health concerns for adulthood.
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NORMAL MENSTRUAL CYCLES
of breast development, the interval to menarche is
longer (3 years or more) than in girls with later on-
Menarche
set.11–13 By 15 years of age, 98% of females will have had
From the early 1800s to the mid-1950s, menarche oc-
menarche.3,14
cured at increasingly younger ages in the United States,
Traditionally, primary amenorrhea has been defined
but there has been no further decline in the last 40 to 50
as no menarche by 16 years of age; however, many
years. This finding also has been seen in international
diagnosable and treatable disorders can and should be
studies of other developed urban populations.2 The US
detected earlier, using the statistically derived guideline
National Health and Nutrition Examination Surveys
of 14 to 15 years of age.3,14 Thus, an evaluation for
have found no significant change in the median age at
primary amenorrhea should be considered for any ado-
menarche over the past 30 years except among the
lescent who has not reached menarche by 15 years of
non-Hispanic black population, which has a 5.5-month
age or has not done so within 3 years of thelarche.
earlier age at menarche than it did 30 years ago.3 Age at
Accordingly, lack of breast development by 13 years of
menarche varies internationally and especially in less
age also should be evaluated.15
developed countries; in Haiti, for example, the mean age
at menarche is 15.37 years.4,5 This knowledge may be
Cycle Length and Ovulation
especially pertinent for practitioners with a large num-
Menstrual cycles are often irregular through adoles-
ber of immigrant families in their patient population.
cence, particularly the interval from the first to the sec-
Although onset of puberty and menarche typically occur
ond cycle. According to the World Health Organization’s
at a later age in females from less well-developed na-
international and multicenter study of 3073 girls, the
tions, 2 large studies have confirmed that a higher gain
median length of the first cycle after menarche was 34
in body mass index (BMI) during childhood is related to
days, with 38% of cycle lengths exceeding 40 days.
an earlier onset of puberty.6,7 This earlier onset of pu-
Variability was wide: 10% of females had more than 60
berty may result from attainment of a minimal requisite
days between their first and second menses, and 7% had
body mass at a younger age. Other possible explanations
a first cycle length of 20 days.16 Most females bleed for 2
for the perceived trend in timing and progression of
to 7 days during their first menses.17–19
puberty are environmental factors, including socioeco-
Early menstrual life is characterized by anovulatory
nomic conditions, nutrition, and access to preventive
cycles,20,21 but the frequency of ovulation is related to
health care.8
both time since menarche and age at menarche.21–23
Despite variations worldwide and within the US pop-
Early menarche is associated with early onset of ovula-
ulation, median age at menarche has remained relatively
tory cycles. When the age at menarche is younger than
stable, between 12 and 13 years, across well-nourished
12 years, 50% of cycles are ovulatory in the first gyne-
populations in developed countries. The median age of
cologic year (year after menarche).
females when they have their first period or menarche is
By contrast, it may take 8 to 12 years after menarche
12.43 years (see Table 1).3 Only 10% of females are
until females with later-onset menarche are fully ovu-
menstruating at 11.11 years of age; 90% are menstruat-
latory.23 Despite variability, most normal cycles range
ing by 13.75 years of age. The median age at which black
from 21 to 45 days, even in the first gynecologic year,16–18
female adolescents begin to menstruate is earlier (12.06
although short cycles of fewer than 20 days and long
years of age) than the median age for Hispanic (12.25
cycles of more than 45 days may occur. Because long
years of age) and non-Hispanic white (12.55 years of
cycles most often occur in the first 3 years postmen-
age) females.3 Although black girls start to mature earlier
arche, the overall trend is toward shorter and more
than non-Hispanic white and Hispanic girls, US females
regular cycles with increasing age. By the third year after
complete secondary sexual development at approxi-
menarche, 60% to 80% of menstrual cycles are 21 to 34
mately the same ages.9
days long, as is typical of adults.16,18,24 An individual’s
Menarche typically occurs within 2 to 3 years after
normal cycle length is established around the sixth gy-
thelarche (breast budding), at Tanner stage IV breast
necologic year, at a chronologic age of approximately 19
development, and is rare before Tanner stage III devel-
or 20 years.16,18
opment.10 Menarche correlates with age at onset of pu-
Two large studies, one cataloging 275 947 cycles in
berty and breast development. In girls with early onset
2702 females and another reporting on 31 645 cycles in
656 females, support the observation that menstrual
cycles in girls and adolescents typically range from 21 to
TABLE 1
Normal Menstrual Cycles in Young Females
approximately 45 days, even in the first gynecologic
Menarche (median age): 12.43 years
year.25,26 In the first gynecologic year, the fifth percentile
Mean cycle interval: 32.2 days in first gynecologic year
Menstrual cycle interval: typically 21–45 days
for cycle length is 23 days and the 95th percentile is 90
Menstrual flow length:
7 days
days. By the fourth gynecologic year, fewer females are
Menstrual product use: 3–6 pads/tampons per day
having cycles that exceed 45 days, but anovulation is still
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significant for some, with the 95th percentile for cycle
PCOS accounts for 90% of hyperandrogenism among
length at 50 days. By the seventh gynecologic year,
females and, by definition, is characterized by amenor-
cycles are shorter and less variable, with the fifth per-
rhea and oligomenorrhea. Before the diagnosis is con-
centile for cycle length at 27 days and the 95th percentile
firmed, hyperprolactinemia, adrenal and ovarian tu-
at only 38 days. Thus, during the early years after men-
mors, and drug effects (such as those caused by danazol
arche, cycles may be somewhat long because of anovu-
and several psychotropic medications) must be ruled
lation, but 90% of cycles will be within the range of 21
out. Additionally, although uncommon in the general
to 45 days.16
population, congenital adrenal hyperplasia should be
ruled out by a negative 17- -hydroxyprogesterone test
ABNORMAL MENSTRUAL CYCLES
result (serum concentrations less than 1000 ng/dL).27
Treatment of PCOS should target menstrual irregulari-
Prolonged Interval
ties, hirsutism if present, obesity, or insulin resistance.
A number of medical conditions can cause irregular or
Menstrual irregularities can be caused by disturbance
missed menses in adolescents. Although secondary am-
of the central gonadotropin-releasing hormone pulse
enorrhea has been defined as the absence of menses for
generator as well as by significant weight loss, strenuous
6 months, it is statistically uncommon for girls and ad-
exercise, substantial changes in sleeping or eating habits,
olescents to remain amenorrheic for more than 3
and severe stressors. Menstrual disturbances also occur
months or 90 days—the 95th percentile for cycle length.
with chronic diseases, such as poorly controlled diabetes
Thus, it is valuable to begin evaluation of secondary
mellitus; with genetic and congenital conditions, such as
amenorrhea after the absence of menses for 90 days.
Turner syndrome; and with other forms of gonadal dys-
Therefore, girls and adolescents with chaotically irregu-
genesis. The diagnosis of pregnancy always should be
lar cycles with more than 3 months between periods
excluded, even if the history suggests the patient has not
should be evaluated, not reassured that it is “normal” to
been sexually active.
have irregular periods in the first gynecologic years.
Irregular menses may be associated with many con-
Excessive Menstrual Flow
ditions, including pregnancy, endocrine disorders, and
A female’s first period usually is reported to be of me-
acquired medical conditions, because all of these condi-
dium flow, and the need for menstrual hygiene products
tions are associated with derangement of hypothalamic-
is not typically excessive. Although experts typically re-
pituitary endocrine function (see Table 2). Commonly,
port that the mean blood loss per menstrual period is 30
polycystic ovary syndrome (PCOS) causes prolonged in-
mL per cycle and that chronic loss of more than 80 mL
tervals between menstrual periods, especially in patients
is associated with anemia, this has limited clinical utility
with signs of androgen excess. The pathogenesis of PCOS
because most females are unable to measure their blood
is unclear; many experts believe that PCOS results from
loss. However, a recent study in adult women confirms
primary functional intraovarian overproduction of an-
that the perception of heavy menstrual flow is correlated
drogen. Others believe that excessive luteinizing hor-
with a higher objective volume of blood loss.28
mone secretion from the pituitary gland, which stimu-
Attempts to measure menstrual blood loss on the
lates a secondary ovarian androgen excess, has a role in
basis of number of pads or tampons used per day or
causing the disorder. Still others hypothesize that PCOS
frequency of pad changes are subject to variables such as
may be related to hyperinsulinism. Whatever its origins,
the individual’s fastidiousness, her familiarity or comfort
with menstrual hygiene products, and even variation
among types and brands of pads or tampons.29 Most
TABLE 2
Causes of Menstrual Irregularity
report changing a pad approximately 3 to 6 times a day,
Pregnancy
although external constraints such as school rules and
Endocrine causes
Poorly controlled diabetes mellitus
limited time between classes may make menstrual hy-
Polycystic ovary syndrome (PCOS)
giene more problematic for adolescents than adults.
Cushing disease
Menstrual flow requiring changes of menstrual products
Thyroid dysfunction
every 1 to 2 hours is considered excessive, particularly
Premature ovarian failure
when associated with flow that lasts more than 7 days at
Late-onset congenital adrenal hyperplasia
Acquired conditions
a time. This type of acute menorrhagia, although most
Stress-related hypothalamic dysfunction
often associated with anovulation, also has been associ-
Medications
ated with the diagnosis of hematologic problems, includ-
Exercise-induced amenorrhea
ing von Willebrand disease and other bleeding disorders,
Eating disorders (both anorexia and bulimia)
or other serious problems, including hepatic failure and
Tumors
Ovarian tumors
malignancy.30–33
Adrenal tumors
The prevalence of von Willebrand disease is 1% in the
Prolactinomas
general population. Von Willebrand disease is the most
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common medical disorder associated with menorrhagia
recommend preventive health visits during adolescence
at menarche.34 As many as 1 in 6 girls presenting to an
to begin a dialogue and establish an environment where
emergency department with acute menorrhagia may
a patient can feel good about taking responsibility for her
have von Willebrand disease.30 Therefore, hematologic
own reproductive health and feel confident that her
disorders should be considered in patients presenting
concerns will be addressed in a confidential setting.36,37
with menorrhagia— especially those presenting acutely
These visits are also an opportunity to provide guidance
at menarche. Hormonal treatment, in the form of estro-
to young females and their parents on adolescent phys-
gen therapy, may affect hematologic factors and mask
ical development based on data that define normal pu-
the diagnosis. Blood collection to screen for hematologic
bertal development, menarche, and menstrual cyclici-
disorders should be obtained before initiating treatment.
ty.38 Even during visits with adult patients who interact
Evaluating the patient may include referral to a hema-
with adolescents or have children, education about ap-
tologist or a specialized hemophilia treatment center for
propriate expectations and normal patterns for the ado-
appropriate screening.
lescent menstrual cycle may be helpful guidance in the
decision to consider evaluation.
ANTICIPATORY GUIDANCE
Asking the patient to begin to chart her menses may
Because development of secondary sex characteristics
be beneficial, especially if the bleeding history is too
begins at ages as young as 8 years, primary care clini-
vague or considered to be inaccurate. Although uncom-
cians should include pubertal development in their an-
mon, abnormalities do occur. Confirming normal inter-
ticipatory guidance to children and parents from this age
nal and external genital anatomy with a pelvic exami-
on. Clinicians should take an ongoing history and per-
nation or ultrasonography can rule out significant
form a complete annual examination, including the in-
abnormalities. Therefore, one might consider the men-
spection of the external genitalia. It is important to ed-
strual cycle as a type of vital sign and an indicator of
ucate children and parents about the usual progression
other possible medical problems. Using menarche or the
of puberty. This includes the likelihood that a child’s
menstrual cycle as a sensitive vital sign adds a powerful
initial breast growth may initially be unilateral and
tool to the assessment of normal hormonal development
slightly tender. Breast development will likely then be-
and the exclusion of serious abnormalities, such as an-
come bilateral, but some asymmetry is normal. Young
orexia nervosa, inflammatory bowel disease, and many
females and their parents should understand that the
other chronic illnesses. Menstrual conditions that sug-
progression of puberty also includes the development of
gest the need for further evaluation are listed in Table 3.
pubic hair, which will increase in amount over time and
Because menarche is such an important milestone in
become thicker and curlier. Additionally, clinicians
physical development, it is important to be able to edu-
should convey that females will likely begin to menstru-
cate young females and their parents regarding what to
ate approximately 2 to 2.5 years after breast develop-
expect of a first period and about the range for normal
ment begins, keeping in mind that recent studies have
cycle length of subsequent menses. Girls who have been
suggested that the onset of both breast development and
educated about early menstrual patterns will experience
menarche may occur slightly earlier for black girls than
less anxiety as development progresses.1 It is equally
for white girls.35 Young females should understand that
important for clinicians to have an understanding of
menstruation is a normal part of development and
bleeding patterns of young females, the ability to differ-
should be instructed on use of feminine products and on
entiate between normal and abnormal menstruation,
what is considered normal menstrual flow. Ideally, both
parents and clinicians can participate in this educational
process.
TABLE 3
Menstrual Conditions That May Require Evaluation
Menstrual periods that:
EVALUATION
● Have not started within 3 years of thelarche
Once young females begin menstruating, evaluation of
● Have not started by 13 years of age with no signs of pubertal development
the menstrual cycle should be included with an assess-
● Have not started by 14 years of age with signs of hirsutism
● Have not started by 14 years of age with a history or examination suggestive
ment of other vital signs. By including this information
of excessive exercise or eating disorder
with the other vital signs, clinicians emphasize the im-
● Have not started by 14 years of age with concerns about genital outflow tract
portant role of menstrual patterns in reflecting overall
obstruction or anomaly
health status. Clinicians should ask at every visit for the
● Have not started by 15 years of age
first date of the patient’s last menstrual period. Clinicians
● Are regular, occurring monthly, and then become markedly irregular
● Occur more frequently than every 21 days or less frequently than every 45
should convey that the menstrual cycle is from the first
days
day of a period to the first day of the next period and
● Occur 90 days apart even for one cycle
may vary in length.
● Last 7 days
Both the American Academy of Pediatrics and the
● Require frequent pad/tampon changes (soaking more than 1 every 1–2
American College of Obstetricians and Gynecologists
hours)
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and the skill to know how to evaluate the young female
ACKNOWLEDGMENTS
patient appropriately.
The committees would like to thank Lesley Breech, MD;
Angela Diaz, MD; S. Paige Hertweck, MD; Paula Adams
AAP COMMITTEE ON ADOLESCENCE, 2005–2006
Hillard, MD; and Marc Laufer, MD; for their assistance in
Jonathan D. Klein, MD, Chairperson
the development of this document.
Michelle S. Barratt, MD
Margaret Blythe, MD
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