STANFORD, CALIF. — A teenage patient complains of “heavy” menstrual periods. Her mother mentions that her daughter never gets periods during soccer season.
Should you evaluate the girl for abnormal uterine bleeding?
Test your knowledge of what's normal or abnormal for teenage menstruation by taking the true or false quiz (see box) before reading commentary provided by Dr. Paula J. Hillard at a pediatric update sponsored by Stanford University.
Puberty and menarche generally arrive several months earlier for African American girls than for white girls, studies in the past decade have shown. While only 7% of white girls had “early” breast development or pubic hair by age 7 years, this occurred in 27% of African American girls, one study found (Pediatrics 1997;99:505–12).
Guidelines suggest not evaluating for precocious puberty unless breast development or pubic hair occurs before age 7 years in white girls or before age 6 years in African American girls. If there are other signs or symptoms such as severe headache or neurologic symptoms, however, an evaluation is in order, said Dr. Hillard, professor of obstetrics and gynecology at the university.
The age at which girls start their periods has been declining since 1800. Declines in the age of menarche up until the 1960s resulted from positive changes such as better nutrition and less infectious disease. Since then, however, declines in the age of menarche seem to be related to negative changes such as overeating and limited physical activity.
Over the past 20 years, the age of menarche declined by 2 months in white girls and by more than 9 months in African American girls. Federal data in 1999–2002 showed the average age of menarche to be 12.5 years in whites and 12.1 years in non-Hispanic blacks and Mexican Americans (J. Pediatr. 2005;147:753–60). The duration of menstrual bleeding has held steady, lasting 2–7 days per period in 92% of teen girls. “Early” or “late” menarche can be defined as 2.5 standard deviations from the mean (ages 9 or 15 years for white girls), said Dr. Hillard, who did not have similar data for African American girls.
An evaluation would be appropriate if a girl has no menses by age 15 years. An evaluation also is warranted if there's no breast development by age 13 years, if menses haven't started 2.5–3 years after breast development, if there are signs or symptoms of pregnancy, or if the patient is 14 years old with obesity, acne, and hirsutism.
Consider polycystic ovarian syndrome (PCOS), anorexia nervosa, or other eating disorders as possible causes. If the mother says her daughter never gets periods during soccer season, “this may be cause for concern,” Dr. Hillard said.
Early menstrual cycles in a girl's life may be anovulatory and shorter or longer than some others; they should not be chaotically irregular.
Most cycles average 21–45 days in the first gynecologic year and trend toward shorter, more regular cycles with age. A 90-day cycle still falls within the 95th percentile during the first year of menarche. Beyond 90 days, evaluate for PCOS, eating disorders, thyroid disease, hyperprolactinemia, gonadal dysgenesis, or premature ovarian failure.
The True or FalseMenstruation Quiz
The age of puberty has been declining.
Pubertal development at about age 8 years constitutes precocious puberty.
Girls begin menstruating at an average age of 13 years.
The age of menarche has been declining.
Normal menstrual periods last 2–7 days.
A girl who has not started menstruating by age 15 years should be evaluated.
In the first year of menses, it's normal to have chaotically irregular cycles.
Menstruation typically cycles every 21–45 days, but a 90-day cycle also is normal.
Quiz Answers: 1. True 2. False 3. False 4. True 5. True 6. True 7. False 8. True