The present invention disclosed a method to detect pregnancy and identify pseudopregnancy, pregnancy and pregnancy loss using ceruloplasmin as a non-invasive marker in animal urine samples. More specifically, this invention provide provides a method to use a non-invasive marker of inflammation, the acute phase protein ceruloplasmin, in urine samples to detect pregnancy and to distinguish between pregnancy and pseudopregnancy in mammals. The steps of this method include: collecting fresh urine sample from a mammal, adding a ceruloplasmin substrate to the urine sample, measuring oxidase activity of said ceruloplasmin through a sequential reading of absorbance of a photometric product using a spectrophotometer to determine the concentration of ceruloplasmin in the at least one urine sample.