Intracytoplasmic sperm injection (ICSI) is a novel technique assisted reproduction whereby a sperm into an oocyte injected with a microneedle. The difference with conventional in vitro fertilization is not the traditional incubated sperm with the egg for fertilization to occur, but is forced by injecting the sperm fertilization. But the probability of success is the same for both procedures have in common that the patient should be submitted in both techniques to a previous ovarian stimulation. Intracytoplasmic sperm injection is indicated when a man has a concentration of very small or low sperm mobility, when it has undergone a vasectomy, when presenting an infectious or infertility causes immune disease, among others.