In all groups blood samples were taken at the 24th hour after delivery and oxytocin and prolactin levels were measured. Plasma of blood samples taken before and after delivery were stored at a temperature of -80°C. Prolactin levels were determined with chemiluminescense immunoassay technique Cobas e 601 (Roche® Diagnostics, Mannheim, Germany) using a commercial kit (Roche®). Oxytocin levels were determined with a commercial ELISA kit (Cusabio Biotech CO. Ltd). By all patients onset time of lactation was recorded.