Everyone knows that in early pregnancy (though sometimes later too) a woman may suffer from gastrointestinal trouble, particularly nausea and vomiting. Few, however, ask themselves what the connection is between pregnancy, which involves the reproductive system, and symptoms that involve the digestive system. The answers to this question can help the expectant mother, because learning the origin of her discomfort allows her to accept it with greater peace of mind.
From a medical standpoint, the cause of the problem lies in the rise of pregnancy hormones, particularly chorionic gonadotropin, produced by the embryo and circulating in the woman's body from the moment of fertilization, which intensifies the peristalsis of the digestive organs. The resulting onset of unpleasant symptoms is therefore both a sign and a guarantee that the pregnancy is progressing well.
From a psychological point of view, the gastrointestinal symptoms of pregnancy connect back to the infantile sexual theories that are part of the adult unconscious. Known to psychoanalysis since 1905 (when Freud first set them out in the Three Essays on the Theory of Sexuality), these theories reveal the explanations children come up with about conception and birth in order to answer the fateful question «how does the baby get in and out of mommy's body?», since they know nothing of the function of semen or the existence of the vagina. The inside of the body is simply imagined as one large empty cavity (able to hold food, babies, or feces indifferently) connected to the outside by a single opening encompassing the anus, urinary meatus, and vagina: the cloaca.*
Conception and childbirth are thus associated with everyday acts like eating and defecating, as many fairy tales suggest, in which the ingestion of some particular substance is followed by the birth of a child.
This infantile logic is reactivated during pregnancy through the woman's unconscious regression to an undifferentiated embryonic state. It is as if forgotten but indelible traces were reawakened in the pregnant woman, erasing the time elapsed between the pregnancy in which she herself was gestated and the one in which she is now the one gestating. This creates a confusion between the two systems, so that many pregnant women respond, with one system, to the upheaval that fertilization has created in the other. The future child, however wanted and desired, is still made up of cells different from the mother's own, since it forms from the fusion of an egg and a sperm cell: a graft foreign to the uterus that must host it, which defends itself by attempting rejection and expulsion. These are physiological, neutral mechanisms that have nothing to do with affection for the future baby, present to a greater or lesser degree in every pregnant woman, who experiences them unknowingly, without realizing it and without any way of influencing them.
These attempts, present in every pregnant woman, play out differently depending on their intensity and on the psychobiological makeup of the mother-to-be: directly, through expulsion via miscarriage; indirectly, through gastrointestinal symptoms; or without the woman even realizing it, through dreams typical of pregnancy.
* On the evolutionary scale, various animal species below mammals have the cloaca as the single opening into which the endings of the intestinal, urinary, and reproductive tracts converge.
** Until the 25th day after fertilization, the primordial germ cells (which give rise to eggs and sperm) are not yet differentiated from the wall of the primitive gut.