Patients with history of gestational diabetes (GDM) are at high risk for developing diabetes mellitus (DM) after pregnancy. This study investigates the rate of GDM patients who received screening and the prevalence of DM in the early post-partum period. Materials and methods: This study included 78 patients diagnosed and treated for GDM between January 2005 and December 2007. They were evaluated whether or not they were screened with 75 g oral glucose tolerance test (OGTT) or fasting blood glucose measurement at post-partum 6-12-week period. The rates of DM and impaired glucose tolerance (IGT) were determined. Results: Of 78 GDM patients only 10 (12.8%) patients were screened with OGTT and 27 (34.6%) patients were screened with fasting blood glucose (FBG) measurement. 41 (52.6%) patients did not receive any post-partum screening. Insulin treated patients during pregnancy underwent OGTT more frequently (p = 0.008). We found that 61% of the patients who did not receive any screening test were seen by a doctor for any reason during this period. DM was diagnosed in 50% of patients who underwent OGTT and 7.4% of patients who underwent FBG measurement during early post-partum period (p = 0.013). Conclusion: Despite the fact that GDM is generally strictly and carefully monitored during pregnancy, it is usually neglected in the post-partum period. Insulin treated patients during pregnancy should be informed better for post-partum screening with OGTT. OGTT appears to be a better way of screening to diagnose DM. © 2009 Springer-Verlag.