Despite continuing significant research efforts and an increasing prevalence of preterm labor (PTL) worldwide, a comprehensive understanding of the mechanisms involved remains to be established; such is the complexity of the interactions involved. Closing the knowledge gaps in this field would afford an opportunity to improve mortality and morbidity rates on a global scale. Early identification of pregnancies at risk of PTL would increase the possibility of delaying birth (where appropriate) prior to initiation of labor. This requires identification of appropriate biomarkers that are readily detectable in easily obtained clinical samples. A family of arachidonic acid metabolites, called eicosanoids. Eicosanoids have shown promise as possible diagnostic biomarkers for PTL. The inherent problems of antibody cross-reactivity in immunoassay methods has, however, resulted in possible misinterpretation of past results. The following mini-review outlines the necessity of such diagnostic targets and the problem with previous research methods and also summarizes recent findings in the field.