Darcy used to have them 5-6 times a day for at least 1/2 an hour. She was a wriggler too. She had them heaps when she was born too and still gets them at least once a day for about an hour. Doesn't seem to bother her though.
I read somewhere that excessive hiccoughs is a sign of reflux. Don't know how true that is, but it's spot on for my Dragon!