Episode 31 – Hypothalamic Amenorrhea

Key Topics Covered

Definition

  • Hypothalamic – Hypothalamus (part of the brain that controls hormones)
  • Amenorrhea – Absence of the menstrual cycle
  • Essentially Hypothalamic Amenorrhea (HA) is a lack of menstrual cycle due to hormones.

Mechanism

The hypothalamus suppresses the production of GnRH, leading to FSH, LH, and oestrogen all being reduced which results in ovulation and menstruation ceasing. It can be due to:

  • Weight loss
  • Stress
  • Over-exercise
  • Or a combination of the above

Contraception could mask this. Many could be experiencing this condition, however wouldn’t know they have it because they wouldn’t get their period anyway. This is a concern as the negative side effects will continue to proceed without the individual knowing.

Negative Side-Effects

  1. Difficulty conceiving – Irregular menstrual cycles makes it extremely difficult to get pregnant.
  2. Bone health – HA causes an overall reduction in oestrogen, which causes the bone to break down. It also decreases calcium absorption and vitamin D function, decreasing bone strength.
    • A woman with 6 months of HA has the bone strength equivalent to a 51-year-old woman.
  3. Illness – HA decreases one’s immune system, making them more prone to colds and illness.
    • For athletes, this is a concern as it decreases their time training at 100% and thus performance at competition time.
    • Limit recovery & ability to make training adaptations. Ie. muscle growth, more injuries.

How Does It Occur?

  • Mainly – Due to weight loss, stress, over-exercise or a combination.
  • Low energy availability – We eat and burn a certain amount of calories, how much is leftover for menstruation to occur?
    • Eg. You eat 2000cal/ day, then burn 1000cal through training. This means 1000cal left for ALL your body’s functions, most individuals’ BMR is over 1000cal. This means not enough calories will be available for your period to occur.
    • Body fat can be broken down and used as energy to support one’s period. In saying this, low energy availability can occur in individuals with a higher level of body fat as well.
    • HA is not purely dependent on body fat percentage. Those who naturally sit at lower levels of body fat may not have HA and vice verser.
  • Lower carb and fat intake – When individuals have a higher intake of protein and fiber, it can naturally decrease their caloric intake as these nutrients are more filling.
    • There are arguments for the role that dietary fat has on hormone production, however, you only need a small amount to cover your bases. This likely has less of an effect compared to the others mentioned.
    • Studies mention the role carbohydrates and glycogen play. Saying that having these preferred types of fuel available is more beneficial. But once again, this likely won’t have a large effect.
  • Fasting and fasted exercise – Increases cortisol (stress hormone), which plays a role in HA.
    • A study found that spending long periods of time without eating seemed to be linked with amenorrhea even when energy balance was similar. That being said it only had 25 participants and the “similar” energy balance was a predicted 659kcal deficit, in comparison to a 313kcal deficit in the group that ate more frequently. It is enough to be useful information, but as mentioned the larger deficit would have been more detrimental.
    • Fasting also makes it difficult to consume enough calories, once again contributing to HA.

 How to Address HA

What you do to undo HA will most likely depend on what’s causing it.

  1. Reduce Exercise – Decreasing exercise volume/intensity can reduce energy expenditure and stress on the body.
    • If your exercise intensity is not very high, this probably won’t affect you.
  2. Increase calorie intake –The REFUEL study found that an increase of just 300-360 calories per day is enough for many people with HA to resume their period. 
    • Many individuals recommend increasing caloric intake by 2500kcal per day, but this is alot.
    • Aiming for 45kcal/kg of lean mass is also recommended. This would still need to be individualised based on needs and training loads.
    • Otherwise, getting back to original body weight or 1-2kg heavier than you were, before losing your period can also be effective.
  3. Eat frequently and adequately – This involves not fasting, which will allow you to achieve maintainance calories easier.
  4. Avoid low intake of any macronutrient– especially fats.
  5. Reducing overall stress –  Cognitive behavioural therapy (CBT) has shown to be a beneficial way of doing this. It might also be relevant if there are disordered eating habits.
    • A study on CBT in 16 people with HA found that 87% resumed ovarian activity over 20 weeks – whereas only 12.5% in the control group did. 

What to do if your sport pretty much requires a level of leanness that typically leads to HA?

  • We try to avoid this where possible. However, it may be something to consider for marathon runners or bodybuilders.
  • Try nutritional periodisation – Intentionally increase your body fat after competition to restore your period.
    • Trent Stellingwerf has a great example with his wife (marathon runner) where they did this over a 4-year cycle to ensure she didn’t experience the consequences of HA lasting long term over a 9-year period.
    • Restoring the period can take up to 6 months. Recovering from HA can take between 3-6 months.

Relevant Links/ Resources

Studies Mentioned

Useful Resources

Relevant Blog Posts