Pediatric emergency medicine trisk 2152 2152

AUB refers to irregular, prolonged, or excessive menstrual bleeding unrelated to
pregnancy. The term AUB has replaced the previous terminology of
dysfunctional uterine bleeding. The majority of adolescents who present to the
ED with AUB will have bleeding related to anovulatory cycles. Normal menstrual
cycles in an adolescent may range from 21 to 45 days, though the adult menstrual
cycle is generally 21 to 35 days. Regular ovulatory cycles may not occur until 3
to 4 years after menarche, with the majority of AUB within the first 18 months
after menarche being due to anovulatory cycles. Bleeding that persists beyond 9
days, recurs at intervals of fewer than 21 days, soaks greater than one pad per
hour for more than 2 hours in a row, produces large-sized clots, causes
symptomatic anemia, or creates hemodynamic instability, warrants attention.
Ovulation typically occurs 14 days prior to the onset of menses, and the
ovarian follicle forms a corpus luteum (type of functional ovarian cyst) that
secretes progesterone and estradiol. After ovulation, the progesterone produced
by the corpus luteum promotes growth of the endometrial secretory glands and
spiral blood vessels, though it also limits the ultimate thickness of the
endometrium. As the corpus luteum degenerates, circulating levels of estrogen
and progesterone fall which lead to endometrial necrosis and menstrual
sloughing, which comprises the menstrual blood flow.
The majority of adolescents who present with AUB experience intervals of
anovulation. Without ovulation, there is no progesterone secreted by the corpus
luteum to promote structural integrity of the endometrium. Estrogen levels
secreted by the ovarian follicles may fluctuate; when large amounts are secreted,
there is greater endometrial proliferation and thus heavier vaginal bleeding.

Clinical Manifestations
History, physical, and laboratory tests help the clinician guide the severity of the
patient’s vaginal bleeding. Bleeding that has been occurring for 8 days or more, at
intervals more frequently than every 21 days, bleeding greater than 80 mL
menstrual period, or bleeding large clots that are at least quarter sized, should be
evaluated by a healthcare provider for AUB. Pertinent history should also include

a pregnancy risk assessment (last sexual intercourse, dates of last two menstrual
periods, contraceptive use history), presence of sexual activity, or presence of any
underlying platelet or bleeding disorder (e.g., thrombocytopenia, von Willebrand
disease).
The physical examination starts with the measurement of the patient’s vital
signs, including checking for orthostatic changes in the pulse and blood pressure.
Pallor and symptomatic orthostasis are concerning for significant anemia.
Petechiae, bruising, and mucosal bleeding may indicate a bleeding disorder. Signs