Premature rupture of membranes is a common complication during pregnancy, which can easily lead to intrauterine infection of the fetus and preterm delivery. The main causes of premature rupture of membranes include the following aspects:

First, the most common cause is an infection in the vagina, which then leads to an ascending infection, triggering chorioamnionitis. When chorioamnionitis occurs, the fragility of the membranes increases, making them prone to rupture, leading to the leakage of amniotic fluid.

Second, the membranes can rupture due to a blunt impact on the abdomen, such as an accidental strong hit, which can cause the membranes to suddenly break, leading to premature rupture of membranes.

Third, an excessive amount of amniotic fluid, due to various reasons, can increase the pressure inside the amniotic cavity, potentially leading to spontaneous rupture of the membranes. These are the various reasons for premature rupture of membranes.