This paper refers to a pair mother-baby psychological support, having as objective to discuss the implications of a possible obsessive neurosis on the maternal functioning of a primipara woman, from a psychoanalytical theoretical referential. In the course of five months, we noted her difficulties in dealing with motherhood and we understood that her possible obsessive neurosis was intensively involved in these difficulties. Troubles in communication, hesitation in anticipation, failures in operation presence-absence, coupled to a whole obsessive symptomatology, guided her maternal functioning. Mainly, we realized her great difficulty, as mother, to ensure the desiring subject condition to her baby.