We aimed at identifying a suitable data analysis approach to investigate potential patterns in the current medical coding in obstetrics and perinatal care. We processed the data reported for 2006 in DRG files from three Romanian university clinics of obstetrics-gynaecology and found substantial differences in the coding practices. Based on the evidence we found with a poor usage of the coding instruments, we concluded that using objective methods and quantifiable measures in analyzing the medical coding could help putting things into the right perspective and bring support for the need for formal education of medical record administrators and coders where such programmes do not exist, e.g. in Romania.