A review of 345 consecutive cases of patients under the age of 40 years with central serous chorioretinopathy seen between 1969 and 1979 was performed in order to define temporal patterns of occurrence. The monthly distribution of cases significantly differed (p less than 0.01) from an expected random distribution. Although a statistical trend analysis failed to confirm a definite seasonal variation (p less than 0.01), an increased number of cases were seen in March and April.