When a human being comes into the world, he is profoundly premature, even if born at term. He does not know that he exists and is not able to survive without the presence of someone to care for him. At the start of his life, negative sensations of pain, disorientation, and anguish prevail: crying expresses his difficulty breathing, the sense of heaviness he feels as he passes from a liquid environment to a gaseous one, the hunger that creates a strong, painful tension he is not yet able to relieve through the mental representation of food. If he is not helped to overcome them, these sensations leave indelible traces in his psyche that can resurface later in certain mental illnesses.

One can understand, then, how important a gratifying fusional relationship with the mother is in the first four or five months of life, experienced as part of himself, as an extension of himself that allows him to survive. From this very close bond, however, he must then emerge; otherwise he remains entangled in a state of confusion with the mother that does not allow him to develop his own individuality. The more satisfying this relationship has been for both members of the dyad, the more able they will be to face, without too much difficulty, the next necessary stage of development.

The bond between mother and baby that characterizes the first months of life (which mothers often forget they experienced) is called by Winnicott (English pediatrician and psychoanalyst) "primary maternal preoccupation".

It is described as a particular psychological condition of the mother concerning the end of pregnancy and the first weeks of the baby's life; it is characterized by extreme sensitivity that allows the woman to attune herself to her baby, to understand his needs, his moods. If it were not linked to birth, this state might seem pathological, dissociated; instead it constitutes a sort of "normal illness" in which all maternal attention focuses on the baby, who occupies first place in her thoughts, causing her to forget herself and what is around her.

The baby needs this intense presence of the mother close to him, not only from a practical standpoint regarding care and the satisfaction of primary needs. He needs to feel at the center of his mother's thoughts, of her gaze, her voice, her words even though he does not yet understand them, of the touch of her hands, which little by little make him aware of his own body. He needs to feel his mother's joy in caring for him, in satisfying his desires, because only in this way does he become able to anticipate, through mental representation, the satisfaction to come.

This means that the mother's initial availability strengthens in the baby the certainty of being loved, wanted, gratified, and thus helps him not to experience waiting with a sense of total anguish.

Considering the vital importance of this first period, in which becoming a "subject", a person, depends on the quality of the bond with the mother, it is desirable that the mother prepare herself psychologically to live serenely through the period following birth (even though it will be marked by different rhythms of life) and organize herself so as to be able to devote herself completely to her little one, without letting herself be distracted by too many other interests.