Hypothalamic amenorrhea
Functional hypothalamic amenorrhea is a diagnosis of exclusion caused by stress, weight loss, or excessive exercise disrupting pulsatile GnRH secretion, producing hypogonadotropic hypogonadism with low LH, FSH, and estradiol; first-line treatment is increasing caloric intake and reducing exercise, with transdermal estrogen-progestin replacement added if menses do not return after 6 to 12 months.
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What this article covers
- Overview
A hypothalamic-pituitary-ovarian axis suppressed by energy deficit or stress: functional hypothalamic amenorrhea (FHA) is a form of hypogonadotropic hypogonadism caused by disruption of pulsatile…
- Epidemiology
Disproportionately affects young, active women: it is common in competitive athletes, dancers, and women with disordered eating or restrictive dieting, and clusters with the female athlete triad of…
- Risk factors
Excessive or intense exercise: especially endurance and aesthetic sports (distance running, ballet, gymnastics) with high energy expenditure.
- Pathophysiology
Energy deficit and stress disrupt pulsatile GnRH release: severe caloric restriction, increased energy expenditure, and psychological stress produce a functional (not structural) suppression of…
- Clinical features
Amenorrhea in the setting of excess exercise, energy deficit, or stress: absence of menses for 3 months (prior regular cycles) or 6 months (prior irregular cycles) in a woman with a history of high…
- Differential diagnosis
Pregnancy: the most common cause of secondary amenorrhea overall; excluded first with a urine or serum beta-hCG before any further workup.
- Diagnosis
A diagnosis of exclusion confirmed by the pattern of low gonadotropins and low estradiol in the appropriate clinical setting: the diagnosis of FHA rests on demonstrating low serum LH and FSH with a…
- Management
First, address the underlying energy deficit or stressor with behavioral change, always first-line: increase caloric intake to match energy expenditure and reduce exercise volume; this is the initial…
- Complications
Low bone mineral density and stress fractures: chronic hypoestrogenism combined with low energy availability accelerates bone loss and raises fracture risk, the most clinically significant long-term complication.
- Prognosis
Generally reversible with correction of the underlying trigger: menses and gonadotropin function typically return once caloric intake, exercise volume, and stress are normalized, distinguishing FHA…
- Prevention
Match caloric intake to energy expenditure in athletes and highly active women: maintaining adequate energy availability prevents the onset of FHA, particularly in endurance and aesthetic sports with high training volumes.
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