You can’t always tell; but, in general, once your water breaks, it keeps coming. Ruptured membranes are not just a small gush or a little bit of spotting; if you think your water has broken, clean up and see if the leakage persists. If it does or you are unsure, you probably need to be examined.
Discharge is common in pregnancy but usually never results in more leakage than would fill a small pad or panty liner. If you are getting cervical checks at your later appointments, the gel we use can sometimes appear later as a leakage of fluid but it is usually only a small amount and you would not see continued leakage.
Probably the most common reason why women believe that their water has broken is because they have peed on themselves. Most women cannot believe that they have peed on themselves, especially if they never felt the urge to pee, but in the third trimester with the baby’s head smashed right against your bladder, this is a common occurrence. If it happens on your bed sheets or in your underwear, you won’t always be able to tell that it is urine by smell or color alone. Amniotic fluid has a unique odor that is like a combination of ejaculate and bleach; that may not be helpful if you’ve never smelled amniotic fluid before, but when you do maybe you’ll recognize it.
All of this being said, large gushes with continual leakage after the fact should be assessed at the hospital or your doctor’s office. You may be ready to rock and roll!