Contemporary diagnosis and management of preterm premature rupture of membranes

Abstract

Spontaneous rupture of membranes (ROM) is a normal component of labor and delivery. Premature ROM (PROM) refers to rupture of the fetal membranes prior to the onset of labor irrespective of gestational age. Once the membranes rupture, delivery is recommended when the risk of ascending infection outweighs the risk of prematurity. When PROM occurs at term, labor typically ensues spontaneously or is induced within 12 to 24 hours. The management of pregnancies complicated by preterm PROM (defined as PROM occurring prior to 37 weeks of gestation) is more challenging. Preterm PROM complicates 2% to 20% of all deliveries and is associated with 18% to 20% of perinatal deaths. Management options include admission to hospital, amniocentesis to exclude intra-amniotic infection, and administration of antenatal corticosteroids and broad-spectrum antibiotics, if indicated. This article reviews in detail the contemporary diagnosis and management of preterm PROM.

Keywords: Antenatal corticosteroids; Antibiotics; Premature rupture of membranes; Preterm birth; Preterm premature rupture of membranes.

Figures

Figure 1

AmniSure® ROM test for the diagnosis of ruptured fetal membranes. The AmniSure ROM test (AmniSure® International LLC, Cambridge, MA) is designed to measure the presence of placental alpha microglobulin 1 (PAMG-1), which is abundant in amniotic fluid but almost absent in cervicovaginal fluid in the absence of ruptured membranes. A sample of cervicovaginal fluid is collected using a sterile swab (no speculum) and eluted into a vial containing solvent for 1 minute. The test strip is then placed in a solvent, allowing the sample in the vial to move through the membrane by capillary reaction. The pad region of the test strip has 2 zones, 1 containing anti-PAMG-1 antibodies (test zone) and the other containing anti-IgG (positive control zone). If PAMG-1 is present in the sample, it will interact with the capture antibody forming antigen-conjugate complexes that can be seen as a visible line. In the absence of antigen, no visible line will form. +ve, positive; ROM, rupture of membranes.

Figure 2

Proposed management algorithm for preterm premature rupture of membranes. CBC, complete blood count; FLM, fetal lung maturity test; GBS, group B beta-hemolytic Streptococcus; MFM, maternal-fetal medicine; PROM, premature rupture of membranes; T&S, type and screen test.