Rupture of Membranes

The amniotic membranes form a protective barrier around the fetus and retain the fluid that cushions the fetus, supports movement, and helps protect the umbilical cord. When the membranes rupture, the barrier is no longer intact. Fluid may continue to leak, bacteria have an easier route to ascend, and reduced fluid can contribute to cord compression. Prelabour rupture of membranes, or PROM, means that the membranes rupture before the onset of labour. The timing of rupture and the gestational age determine the clinical branch: - Term PROM: 37 weeks or later. - Preterm PROM, or PPROM: before 37 weeks. - Previable PROM: before 24 weeks. A spontaneous rupture during established labour is not PROM. A patient can have ruptured membranes without contractions, so the absence of labour does not make the finding benign. Conversely, wetness alone does not prove that the membranes have ruptured; urine, vaginal discharge, blood, and semen can look similar. PPROM creates two competing concerns. Remaining pregnant may allow further fetal maturation, but the longer the membranes are open, the greater the opportunity for infection. Latency—the time...