"With this change in procedure, she is now more self-conscious as she now has to decide which panties (style, color, etc.) she should wear. Any suggestions?"
Yeah, go with blue.
Ok, so here comes my advice to someone who had this issue over 7 years ago and hasn't been on zity in 6 years, but since someone resurrected this post 30 minutes ago:
When the movement for overall patient modesty began in the 90's & suddenly they would have paper gowns for my annual physical, i waived wearing them. I was used to seeing the same male doctor every year, & i thought having a gown on was more obstructive, obtrusive. I had been used to being just in my briefs, what was i gonna start wearing a gown for? i can't be out mowing my lawn in nothing but shorts all the time or at public pools in nothing but swimming trunks and then be self conscious for a doctor visit where i know the doctor from previous visits.
So my advice in this situation would be, since she's wearing a gown anyway, is to maintain her traditional level of undress. Sounds like choosing panties is an issue, & she's used to commando under the gown, stay commando. Consider the procedure "panties optional" for the other patients who feel they need them for modesty.
I thought anyone in a similar boat might be able to use this advice as well.