Hypothalamic Amenorrhea (FHA)
Definition - What does Hypothalamic Amenorrhea (FHA) mean?
Hypothalamic amenorrhea is a condition in which menstruation stops (amenorrhea) because of an issue with a region of the brain called hypothalamus.
The hypothalamus produces a hormone called gonadotrophin-releasing hormone (GnRH). GnRH sends signals to a small gland located at the base of the brain, called pituitary gland, which in turn, sends signals to the ovaries that produce the primary female reproductive hormones. Therefore, any problem in the hypothalamus can result in cessation of menstruation, impaired ovulation, and infertility.
In other words, the ovaries fail to produce hormones if the master gland— the hypothalamus —does not direct the pituitary gland to make them.
It affects around 10% of American girls, mostly during their teenage years. Hypothalamic amenorrhea is often a diagnosis of exclusion, which is suspected only after other causes that could be interrupting the menstrual cycle have been ruled out.
FertilitySmarts explains Hypothalamic Amenorrhea (FHA)
In addition to the absence of ovulation and menses and infertility, individuals may experience a poor sexual drive and features of an underactive thyroid, which often accompanies hypothalamic amenorrhea.
These features may include feeling unusually cold and lethargic, brittle hair and nails, constipation etc. Because estrogen is critical for bone strength, these women are at risk for bone loss and repeated fractures.
The following factors put a female at risk of developing hypothalamic amenorrhea:
- Poor diet and being underweight
- Emotional stress
- Extensive exercise, as seen with athletes, ballet dancers, and others who burn more calories than they consume. This causes the stomach to release a hormone called ghrelin, which other than promoting hunger also blocks the interaction between the hypothalamus, pituitary, and the ovaries. In addition, ghrelin prolongs amenorrhea
- Eating disorders such as anorexia nervosa and bulimia nervosa
When an individual presents with amenorrhea, the doctor will first rule out other common causes of amenorrhea such as PCOS and high prolactin levels. If these are negative, the tests are then directed towards diagnosing hypothalamic amenorrhea, for which the blood tests include FSH, LH, estrogen, and TSH levels.
Treatment includes addressing the underlying causes such as reducing stress levels, limiting the intensity of exercise, or increasing the weight and BMI, preferably via behavioral modification.
Hormonal replacement therapy with estrogen and progesterone pills is also essential to prevent bone loss. Vitamin D and calcium are substituted for bone strength.
For impaired ovulation and infertility, the doctor may prescribe medications like pulsatile GnRH or gonadotropins. IVF may be considered if medications don't help.