37 weeks pregnant, why do i feel pulsating in my belly, it's more frequent then hiccups?

Call your OB: At 37 weeks and earlier any ?S like this should be directed to your ob, not here, could be baby moving or hiccups from baby or something else, if u were my pt i would have u come in to make sure everything was ok- most likely is, but never know or go to l&d, no reason to take any chances at 37 weeks so call your OB now and do what they recommend.