Recombinant FSH (r-FSH) used for ovarian stimulation can currently be self-administered either by a conventional syringe or by a pen device. This randomized controlled trial compares the efficacy and convenience of a new, more sophisticated and fully automated injection device (Softinject(trade mark)) with the conventional syringe for r-FSH self-administration. A total of 300 women needing ovarian stimulation for IVF/intracytoplasmic sperm injection were randomized to the automated injector or the conventional syringe group. Patients of both groups had ovarian stimulation with follitropin alpha after pituitary desensitization with a gonadotrophin-releasing hormone agonist. State anxiety score, overall pain score and pregnancy rate were chosen as the main outcome measures. Patients in the automated injector group showed lower state anxiety (P < 0.01) and overall pain (P < 0.01) scores and a comparable pregnancy rate per started cycle as compared with the conventional syringe group. They needed lower doses of r-FSH (P < 0.05) and their stimulation was shorter (P < 0.05). It is concluded that the use of a fully automated injector for r-FSH self-administration reduces pain and stress as compared with the conventional syringe. This device can be used for any subcutaneously administered drug employed in ovarian stimulation.