When a pregnant woman experiences premature rupture of membranes, the sensation is usually a sudden flow of a lot of fluid from the vagina. It may run down the legs, and sometimes the fluid will contain fetal fat and meconium. Some pregnant women also feel intermittent small amounts of vaginal fluid or feel that their vulva is wetter than usual. So most pregnant women will feel this sensation when their membranes rupture prematurely, and a very small percentage will not feel anything at all. The diagnosis of premature rupture of membranes is usually based on the patient’s sensation, history, and examination. When we diagnose premature rupture of membranes, we usually use a vaginal speculum to open the vagina and look at the back of the posterior fornix to see if there is more fluid. If you see fluid coming out of the cervix or if there is more fluid in the posterior fornix and you can see fetal fat-like material, then the diagnosis of premature rupture of membranes is not made. Then there is no problem to diagnose premature rupture of membranes. Alternatively, we can use PH test paper to check the acidity of our vaginal fluid, if it is alkaline, then the diagnosis of premature rupture of membranes is very likely.