Preliminary results with the use of the ROM-check immunoassay in the early detection of rupture of the amniotic membranes

Abstract

The unequivocal presence of amniotic fluid in the vagina is an important clinical sign of rupture of amniotic membranes, entailing impending delivery or risk for chorioamnionitis. Commonly used methods for detection of amniotic fluid in the vagina include pooling, ferning, nitrazine paper, ultrasound measurement of amniotic sac dimensions, dye injection or measurement of prolactin in vaginal secretions. These results are either difficult to interprete or are obtained after an invasive or expensive procedure. Measurement of alphafetoprotein (AFP) in vaginal secretions has also been considered for this application, but has proven unreliable due to its similar concentration in maternal plasma and amniotic fluid in the third trimester of pregnancy. We have evaluated a recently introduced method, the ROM-check Immunoassay (Adeza Biomedical, Sunnyvale, CA, USA) which is based on the detection of a fetal isoform of fibronectin in vaginal secretions when amniotic fluid is present. Our aim was to establish the reliability and clinical efficacy of this test in a number of obstetrical situations with unequivocal or equivocal rupture of the membranes (ROM). We conclude that in cases of unequivocal rupture and/or intactness of membranes, results of the ROM-check Immunoassay correspond well with the clinical findings, whereas in clinically equivocal rupture of the membranes, the test may add proof to the clinical suspicion of ROM but has to be interpreted with caution along with other clinical and non-clinical parameters.