Two cases of colonic pseudo-obstruction (the so-called Ogilvie's syndrome) are reported. Both patients were in the immediate postcesarean section puerperium. The importance of early diagnosis in these cases is stressed, because this complication has a high mortality rate, frequently in relation to delayed diagnosis and treatment. One patient was successfully treated with conservative measures because diagnosis was made early. A plain X-ray abdominal film which shows cecum dilatation, with or without ascending and transverse colon dilatation, and no distal air, makes the diagnosis. A cecum diameter of 9 cm or more is a surgical indication, because the possibility of wall perforation is high. Surgical techniques are: puncture decompression or cecostomy. When cecum diameter is less than 9 cm, non-surgical measures (nasogastric suction, correction of any fluid and electrolytic imbalance, and maybe a flatus tube) are indicated. Observation through repeated X-ray abdominal films shows when the surgical indication appears: (1) failure of the conservative treatment (cecal distension continues or increases); or (2) cecal perforation is documented.