Closed rectum is a very frequently encountered anomaly of the newborns in our university hospital. Before making a rectal opening, the anorectal sphincter muscle needs to be stimulated to prevent any damage to the muscle itself. In this study, we have designed a stimulator that provides reasonably constant output current depending on the physiological impedance of the rectal area. The current amplitude can be set between 20 and 250 mA. Stimulation pulses are adjusted for duration of 230 s and can be obtained at a repetition period between 1.75 and 20 ms. Fifteen patients in the Pediatric Surgery Department of Erciyes University Hospital were subjected to our stimulation tests. On average, about 140 mA was enough to stimulate the muscle when probes were applied over the skin. On the other hand, with the placement of probes beneath the skin, stimulation was obtained for pulse amplitude of 40 mA.