Rupture of membranes (
ROM) or
amniorrhexis is a term used during
pregnancy to describe a rupture of the
amniotic sac. Normally, it occurs spontaneously at
full term either during or at the beginning of
labor. Rupture of the membranes is known colloquially as "
breaking the water" or as one's "
water breaking." A
premature rupture of membranes (PROM) is a rupture of the
amnion that occurs prior to the onset of labor.