I have had one, and it is uncomfortable at the most.. kind of like a pap smear, and then they put the saline in and you don´t feel a thing.. at least I didn´t... I had already had a hystersalpingogram and that one hurt a lot, so this one was just uncomfortable... Just remember to take a pad for afterwards because some saline will remain and then it will drip off during the day... I hope everything goes well and you don´t feel pain or anything like that..