Hello, I had a hsg done in Jan and I too had to take meds befor but I always have problems taking meds I always get a upset belly so I decided to start taking them after I got the hsg, I was fine by doing it that way. I took 2 mortin on my way to the hospital. I had mine on cd7 I think that the only reason they plan it for those days is to insure that you are not pg. Not to scare you but it is not pleasent. It only takes like 5 mins till it is over but try to stay relaxed it does make it a little easer. I wish you all the luck and sending you lots of

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