In the present paper, we examine different obstacles that prevent the teaching efficient of the biology, especially in her aspect of the human reproduction. Thus, at the time of the teaching of this scientific discipline, the matters that don't make the unanimity exist. For some, all matters must be taught to the pupils to the point. While for others, the relative matters to the human reproduction, the sex, etc. must not be taught to the school, to the risk to push the pupil to the experimentation. Of where, it is necessary to wait that the nature teaches them. Reason for which, we wrote this paper to mean to the readers the different obstacles bound to this teaching.