Huge increase in BH before labor?

I'm 37+4 and getting BH contractions like crazy... Anywhere from 2-3 up to 10 an hour since Monday! They ebb and flow and don't hurt or increase in intensity so I know it's just pre-labor (my midwife told me it's just my uterus "getting warmed up"), but just curious if anyone else had a huge increase in BH before labor and if so how long was it before you started getting real contractions?