Objective: To develop a model based on noninvasive parameters to predict the probability of intra-amniotic infection and/or inflammation (IAI) in women with preterm premature rupture of membranes (PPROMs). Methods: Maternal blood was collected for determination of the C-reactive protein (CRP) level and white blood cell (WBC) count immediately after amniocentesis in 171 consecutive women with PPROMs. Intra-amniotic infection and/or inflammation was defined as a positive amniotic fluid (AF) culture and/or an elevated AF interleukin 6 level (≥2.6 ng/mL). Results: A risk score based on a model including maternal blood CRP, WBC, parity, and gestational age was calculated for each patient. The model was shown to have an adequate goodness of fit (P = .516), and the area under the receiver–operating characteristic curve was 0.848, indicating very good discrimination. Conclusion: The noninvasive model based on maternal blood CRP, WBC, parity, and gestational age is highly predictive of IAI in women with PPROMs.