I usually had my trigger shot when they were between 16-20.
On clomid my Doc liked to see them at least 20mm to 23mm.
I am only getting 1 follie every cycle and the last one was 20 day before IUI. Good luck to you
ttl
Steff
i belive mature follies for trigger should be at least 17mm to 22m hope you have a sucessful journey
*:O) erika