Normal discharge and premature rupture of membranes can be differentiated by the color and nature of the discharge as well as routine testing. 1. Color: The color of normal discharge is milky white or light yellow; while the color of amniotic fluid in premature rupture of membranes is colorless, translucent or light yellow. 2. Character: the normal secretion is thick, odorless or has a faint fishy smell; while the amniotic fluid in premature rupture of membranes is odorless, translucent and liquid. The amniotic fluid of pregnant women in the early stages of pregnancy is mostly clarified, while the amniotic fluid of premature rupture of membranes in the late stages of pregnancy is turbid, and some of the metabolites can be seen in suspension. 3. Routine examination: amniotic fluid crystallization and other routine examination can also be used to determine the normal secretion and premature rupture of membranes amniotic fluid. If the test result is positive, it is amniotic fluid with premature rupture of membranes, and if the test result is negative, it is normal secretion. When abnormal vaginal discharge occurs, it is recommended to go to the hospital for examination.