From the Guidelines
The most appropriate next step in management for this 15-year-old girl is E) Reassurance only. This patient presents with primary amenorrhea (no menstrual periods) but shows normal development for her age. Her sexual maturity rating of 3 for breast and pubic hair development indicates that puberty is progressing normally 1. Her vital signs are normal, and her BMI is at the 26th percentile, which is within normal range. The absence of menstruation is likely related to her participation in long-distance running combined with her relatively lean body composition. Female athletes, particularly those in endurance sports like running, commonly experience delayed menarche due to low body fat percentage and the physical stress of intense exercise, which can lead to Functional Hypothalamic Amenorrhea (FHA) 1. This condition is generally not concerning if other development is proceeding normally. Some key points to consider in this case include:
- The patient's age and development stage, as primary amenorrhea is defined as no menarche by age 15 years 1
- The potential impact of exercise and low body fat on menstrual function, as marked reduction in energy availability (EA) may disrupt the hypothalamic-pituitary-gonadal axis 1
- The importance of monitoring and follow-up, rather than immediate hormonal testing, as reassurance and continued monitoring are appropriate in this case Hormonal testing (options A, B, C, and D) would be premature at this stage since she shows no other concerning signs such as growth issues, virilization, galactorrhea, or symptoms of thyroid dysfunction. Reassurance and continued monitoring are appropriate, with follow-up in 6-12 months if menstruation has not begun.
From the Research
Evaluation of Amenorrhea
The patient is a 15-year-old girl who has not had a menstrual period, with no history of serious illness and takes no medications. She participates in long-distance running and has a BMI at the 26th percentile.
- The first step in evaluating amenorrhea is to rule out pregnancy, which is the most common cause of amenorrhea 2.
- A careful history and physical examination may reveal evidence of androgen excess, estrogen deficiency, or other endocrinopathies 2.
- Serum prolactin and thyroid-stimulating hormone (TSH) levels should be checked in all women who are not pregnant 2, 3.
- Given the patient's age and symptoms, it is essential to evaluate her thyroid function and prolactin levels to determine the underlying cause of her amenorrhea 4, 5, 6.
Next Steps in Management
Based on the patient's presentation and the evidence, the most appropriate next step in management would be to check her serum prolactin concentration, as this is a crucial step in evaluating amenorrhea 2, 3.
- The patient's physical examination shows no abnormalities, and her sexual maturity rating is 3 for breast and pubic hair development, which suggests that she may have hypothalamic amenorrhea, a common condition in women with a history of vigorous exercise 2, 3.
- Checking serum prolactin concentration will help determine if the patient has hyperprolactinemia, which can contribute to amenorrhea 4.
- Thyroid function tests may also be necessary, as thyroid dysfunction can be associated with amenorrhea 5, 6.
Appropriate Response
The most appropriate response is to check the patient's serum prolactin concentration, as this is a critical step in evaluating amenorrhea and determining the underlying cause of her symptoms 2, 3, 4.