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Lucy asked...

Exercise and monthly cycles

Hi, I am 31 and have always been very active. In January I increased my exercise to 5-6 days per week for a competition I was training for. Since then I have not had a period. I have always had a relatively long (irregular) cycle, on average a 6 weekly cycle. Since September I reduced my training again and am wondering at what point I should be concerned or visit my GP. I didn't go before as I knew they would tell me it is due to excessive exercising. I have had this before when I came off the contraceptive pill and they ran some tests which identified cysts on my ovaries but they did not think I had PCOS so I don't need to worry. I am just unsure at what point I should be concerned and ask someone to look into it for me. I have obviously done pregnancy tests which have been negative so can rule that out. Thank you.

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The answer

Whenever exercise is increased in either duration or intensity, it can throw your hormones off temporarily.

Exercise places stress on your body, and intense or prolonged exercise performed frequently can cause hormonal changes. These changes might lead to a short-term loss of your period, but more usually your body should adjust to your new workout program and your period should return.

However, if you skip more than three periods or if you experience consistently irregular periods we do normally suggest that you should consult your doctor to determine whether there's another underlying cause of your amenorrhea.

It’s also worth bearing in mind that intense exercise or increased exercise that leads to extreme fat loss can also alter your hormone balance and contribute to secondary amenorrhea (a loss of periods).

While you haven’t mentioned any accompanying weight changes of this nature if you have noted a large amount of weight loss this may also be a contributory cause in addition. Given that you have reduced your exercise programme and are yet to have a period, and the length of time since you last had a bleed, it would seem very sensible to arrange an appointment with your GP to discuss this and seek an assessment.

Answered by the Health at Hand nurses  

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