We go to the hospital 2 weeks prior to our endo appointment. I get the kids up and we go....usually drawn about 8:00 AM,  I just give them their pills cortef and florinef after the draw.  I don’t think waiting to give the pills a couple hours once every three months is a big deal,  but like I said I think as long as you do the  same thing each time,  go about the same time and either do or do not take pills then you can compare apples to apples,  just pick what you feel comfortable with and if you make a change make sure and tell the Endo that you did something different