iGFBP-1 Rapid Test Cassette (Vaginal Secretion): Performance Characteristics and Clinical Application in Detecting Rupture of Fetal Membranes

The iGFBP-1 Rapid Test Cassette (Vaginal Secretion) is a visually interpreted, qualitative immunochromatographic assay designed for the detection of insulin-like growth factor-binding protein 1 (iGFBP-1) in vaginal secretions of pregnant women. As a major protein marker of amniotic fluid, iGFBP-1 serves as an indicator for the diagnosis of rupture of fetal membranes (ROM). This study aims to do clinical studies of iGFBP-1 Rapid Test Cassette (Vaginal secretion) with the iGFBP-1 positive specimens and negative specimens which confirmed with other Rapid Test. A total of 230 vaginal swab specimens (100 iGFBP-1 positive and 130 iGFBP-1 negative, confirmed by another commercial iGFBP-1 rapid test) were analyzed. The results demonstrated high relative sensitivity (98.0%, 95%CI: 93.0%-99.8%), relative specificity (97.7%, 95%CI: 93.4%-99.5%) and overall accuracy (97.8%, 95%CI: 95.0%-99.3%). Intra-assay and inter-assay precision were excellent, with >99% correct identification of specimens across three lots. No cross-reactivity was observed with common vaginal microorganisms and no interference was detected from substances such as globulin, hemoglobin or bilirubin at clinically relevant concentrations. These findings indicate that the iGFBP-1 Rapid Test Cassette is a reliable, rapid, and practical tool for the qualitative detection of iGFBP-1 in vaginal secretions, aiding in the timely diagnosis of ROM and supporting clinical decision-making in obstetric care.