As you approach your due date, the painless and infrequent Braxton Hicks contractions that you may have been feeling since mid-pregnancy sometimes become more rhythmic, relatively close together, and even painful, possibly fooling you into thinking you're in labor. But unlike true labor, this so-called false labor doesn't cause significant, progressive dilation of your cervix, and the contractions don't grow consistently longer, stronger, and closer together.
Note: Not every woman experiences bouts of false labor. And in some cases, the strong, regular contractions of true labor come on with little or no warning.