Chorioamnionitis (CA) is an intra-amniotic infection which commonly occurs following Premature Prolonged Rupture of the Membranes (PPROM). This study investigated the use of Modified Early Warning Scores (MEWS) as a possible early prediction tool for the development of CA following PPROM via a retrospective, observational study of selected patients who had suffered PPROM in an Australian teaching hospital between September 2008 and January 2011. Of the 88 patients identified, 68 patients had histological evidence of CA (PPROM + CA) and the remaining 20 formed the control group (PPROM). When comparing PPROM+CA to PPROM alone, a MEWS of ≥ 1 was shown to have a sensitivity of 0.896 (95% CI 0.8-0.948), a specificity of 0.421 (95% CI 0.23-0.637) and positive and negative likelihood ratios of 1.547 (95% CI 1.1-2.29) and 0.248 (95% CI 0.1-0.6) respectively. A ROC curve established an Area Under the Curve (AUC) of 0.690 (p < 0.05), suggesting that within the population of adult women experiencing PPROM who are between 20 and 37.86 weeks gestation the highest MEWS within the 72h before delivery is a valid diagnostic aid with regards to CA.