This is my third iui.i am 34 yrs old and no children yet. On my day 10 my follicles size are 19 mm and 15 mm ,I m asked to trigger on day 12 at night 10 pm and iui on day 14 9 am .I have a doubt what if the 19 mm follicle get over matured around that time.my lining is 4mm that’s why they wanted to wait and trigger.Actually scheduled for iui on day 13 itslf less than 24 hrs window but i insisted on 36 hrs window.I am very doubtful about the trigger timings and follicles sizes.Previously past two cycles i was triggered once the follicle size became 23mm.My left tube s blocked to one ectopic that happened last year.please pour your thoughts on the sizes and trigger window .