Late ovulation on ovulation induction medication?

[CoralCats]

Hi everyone,

I'm in my first month of ovulation induction medication (Clomid or Letrozole which is unknown due to a study I'm participating in). I had the follicle tracking scan on cycle day 13 and I had 2 follicles at around 17.7mm and was told I'd ovulate in the next 24-48 hours. On my home ovulation test kit I didn't ovulate until day 17. Based on a follicle growth of 2mm a day the follicles would have been around 28mm. I'm unsure if that's too large and unlikely to release a viable egg. Having PCOS I usually ovulate late but day 17 is the earliest I've ovulated in the past but had no luck. I don't know what benefit Clomid/Letrozole is bringing when I'm ovulating late still? If the follicles were large enough on day 13 why am I not ovulating when they expect me to? Do you think I need a trigger shot for ovulation? Been TTC for 18 months so not sure what's wrong other than PCOS but I do ovulate most months, just late.

Thanks!

[DianeArnold Partner Nurse Fertility Network UK]

Hi CoralCats. Having PCOS would probably be the eason your leading follicle is smaller, but is acceptable. I would go by the scanning sizes to be sure. Good luck! Diane