Premature rupture of membranes (PROM) is the rupture of membranes before the onset of labor. Membrane rupture before labor and before 37 weeks of gestation is referred to as preterm premature rupture of membranes (PPROM). PPROM is far more difficult to manage than PROM at term. The best possible approach to clinical assessment and treatment of women with term and PPROM remains controversial. The management of PPROM depends on the balance between the risks for fetal and neonatal complications with immediate delivery versus the risks and benefits of conservative treatment. Expectant management of preterm PROM and twin pregnancies with PPROM are also discussed in this chapter.