Biomarker testing has arrived in Obstetrics. Of course, we have been using some biomarkers for years, like PAMG1 (Amnisure) and AFP+ILGFBP1 (ROM Plus) for ROM evaluation. In May 2023, the FDA cleared Thermo Fisher Scientific's maternal serum biomarker test for prediction of preeclampsia with severe features in hospitalized patients (and we have a prior episode on that). Now, as of July 9, 2024, published data has arrived for a new maternal serum biomarker ratio for the prediction of preterm birth in low-risk patients. This is the PreTRM biomarker test. This is on the path for FDA clearance. In this episode, we will review the AVERT Preterm Trial which utilizes a novel biomarker ratio using IGFBP4/SHBG. What did this study find? There some promising aspects to this, and also some striking limitations. Listen in for details!