Testing / menstrual cycle

[Cat45]

Hi again. Thank you very much for all the advice about tests. I understand it’s best to test as early in the morning as possible , however, I also noticed some mention of menstrual cycles ? Please could I check what that’s about ? Thank you in advance x

[jimh111]

TSH varies considerably during the menstrual cycle frontiersin.org/articles/10... , see Figure 1. This means we shouldn’t pay excessive attention to TSH. I’m not in favour of trying to get an elevated TSH result, not least because some of the worst cases of hypothyroidism are caused by a TSH that is too low.

[hjh88]

Yes TSH does vary with the menstrual cycle. It’s highest during ovulation and lowest during menstruation.

If you happen to have a GP who is wedded to TSH as a measure of thyroid status, try if you can to get your bloods drawn mid cycle, roughly when you’re ovulating, and with all the usual conditions (early in the day, fasting, adjusted dose times etc).

[jimh111]

Get hold of your previous thyroid test results and post them here. You previous post suggests you may have a low TSH in which case it would be unwise to try and get a higher number.

[hjh88 in reply to jimh111]

Although equally with hypo symptoms it’s possible that it might be beneficial too, particularly with an uncooperative GP. After all, a low TSH can as much be to do with hashimotos as it can graves.

[jimh111 in reply to hjh88]

Sorry don't understand your comment! I'm thinking if the TSH is e.g. 0.5 with low normal fT3, fT4 then things are not normal. If you manage to get a TSH reading of say 0.8 then it will be counter-productive, it will look less unusual. If you know your current TSH then you are in a posistion to move it up or down if you absolutely need to for a diagnosis.