Better early or late for accurate FSH test

[Bear78]

Started my period very very light last night. Had FSH tested today when still very light / dark brown spotting. Wondering whether it will be accurate? Day 2 would have been on the weekend so today seemed closest. Anyone know if its better to do it a bit later or earlier in the cycle? My results were good so that's positive.

[Orla9298]

It has to be day 3 of your cycle but they advise that between 2 to 4 of your cycle is ok. If you’re getting it done to get funding and there is a risk it will be high, go on day 2 as it will be lowest!