We developed a cellular automaton that is able to extract the information about the position of follicles in the ultrasonic image. Follicles are small protective sacs containing ova in the cortex of women? s ovaries, and their ultrasound monitoring is very important in diagnosing and treatment of infertility. The original ultrasonic images were reduced in size and number of colours and then used as the initial state of our cellular automaton. Following the findamental natural principle of attacking/defending, the transition rule has been developed. The results are quite encouraging andprovide a good starting point for firther enhancement and development.