Hi Snowcat,
I’ve got one of the Putnams vulva cushions, I’ve been using it at work to help cope with the burning/stinging pain I have when sitting for long periods of time.
I also thought I needed a bigger hole but I might have been using it the wrong way around with the thinner portion of the hole at the front😳. I’ve since flipped the cushion round so the bigger part of the hole is at the front which helps a bit more.
I did also cut some of the edges off the cushion so it fitted on my office chair better and then sewed up the slack on the cushion cover so it still looks neat and that hasn’t compromised the cushion at all. I would guess that as long as you increased the size of the central hole very gradually it would be ok. I just trimmed mine with a large sharp kitchen knife.
Alternatively, at home when needed, I sit on one of those holiday travel neck pillows, they have some good large solid ones in Tk max at the moment and it takes all the pressure off the vulva area.
I hope this helps