Evaluation and Management of Irregular Menses in Pediatric Patients

Initial Clinical Assessment

The American Academy of Pediatrics recommends obtaining a detailed menstrual and medical history focusing on age of menarche, duration of irregularity, weight changes, eating patterns, and exercise habits to screen for Female Athlete Triad or disordered eating 1
A thorough medical history should include medication use, particularly hormonal contraceptives, antipsychotics, and antiepileptics, as well as symptoms of galactorrhea, hirsutism, or acne suggesting hyperandrogenism 1, 2
Calculating BMI is essential, as obesity is associated with PCOS and menstrual irregularities 1

The Endocrine Society recommends first-line tests, including pregnancy test, FSH, LH, TSH, prolactin, and estradiol, to be performed in all patients with irregular menses 1, 2
Measuring LH/FSH ratio is crucial, as a ratio >2 suggests PCOS 1, 2
Elevated FSH (>40 mIU/mL) indicates primary ovarian insufficiency, requiring confirmation with repeat FSH 4 weeks later 1

Pelvic ultrasound is indicated when clinical features or hormonal tests suggest ovarian pathology, and should be performed transvaginally between days 3-9 of the cycle 1, 2
Assessing endometrial thickness is essential, as a thin (<5 mm) endometrium suggests estrogen deficiency, while a thick (>8 mm) endometrium suggests chronic anovulation with unopposed estrogen 1

The American College of Obstetricians and Gynecologists recommends referring patients to pediatric endocrinology/gynecology if there are no signs of puberty by age 13 years, primary amenorrhea by age 16 years, or failure of pubertal progression 3, 4
Referral is also recommended for patients with menstrual cycle dysfunction suggesting premature ovarian insufficiency, persistent abnormal hormone levels, or severe menstrual irregularities 2, 3, 4

The American Society of Clinical Oncology recommends monitoring growth and pubertal development annually in cancer survivors treated with gonadotoxic chemotherapy or ovarian radiation 3, 4
FSH and estradiol should be measured in patients presenting with menstrual cycle dysfunction, and hormone replacement therapy should be discontinued prior to laboratory evaluation when applicable 3, 4