Hi Lou
So sorry to hear AF arrived early
On our first fresh ivf I started spotting a few days before test day (but actually when AF would've arrived - I have long luteal phase - but obviously not a "natural" cycle so couldn't really take this into consideration)...I tested BFN on test day, didn't bother with the cyclogest that morning and AF arrived within the hour so looks like it was only that "holding" it back.
We've just had a natural FET & although I was again on same 800mg cyclogest (400mg x 2 a day) I started spotting on the day before test day - the actual day AF was due, so again looks like only cyclogest delaying AF from coming fully...I still used the cyclogest cos got a "weird" faint positive on 2nd test (although 3 more tests were negative) but by Saturday more spotting (and yet another negative test) so no cyclogest that day and AF showed up full force (and still is

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All I keep thinking is that AF always seems to turn up bang on time despite having the cyclogest so it is something we will be discussing with our consultant at our follow up appt as I seriously want to try another form of progesterone for our next FET (we've 2 frosties left). I want to see if I can have gestone (or similar) progesterone jabs or even pregnyl jabs which I know they can also do...as I'm concerned that progesterone isn't high enough for me (I have naturally high progesterone levels when been tested for ovulation so I'm wondering if it means I need much higher levels for assisted treatment to keep womb lining from shedding - of that makes sense

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I too was on prednisolone (20mg) & clexane (40mg) and I'm convinced I had implantation pains on 6 & 7dpt (sharp stabbing shooting pains) and then got a very confusing result on test day - had negative at 5.30am but then a faint positive at around midday-ish (don't ask why tested again !!) but I've no idea if this was dodgy test, evaporation line or a "real" faint positive...sadly all since were negative (3 more Friday evening and 1 Saturday morning) and AF showed up full flow on Saturday....I'll never know if was a genuine faint positive or not but I'm concerned about the form of progesterone I've been prescribed for these last 2 cycles.
Anyway, not sure if really helped but I would definitely discuss with your clinic as we're certainly going to....it can't hurt to try something different.
Take care hun....thinking of you...
Natasha x