A well developed woman of 30, who had ten children in twelve years, in the third month of her tenth pregnancy saw a child run over by a street car, which crushed the upper and back part of its head. Her own child was anencephalic and acranial, with entire absence of vault of skull. (F. A. Stahl, American Journal of Obstetrics, April, 1896.)
A healthy woman with no skin blemish had during her third pregnancy a violent appetite for sunfish. During or after the fourth month her husband, as a surprise, brought her some sunfish alive, placing them in a pail of water in the porch. She stumbled against the pail and the shock caused the fish to flap over the pail and come in violent contact with her leg. The cold wriggling fish produced a nervous shock, but she attached no importance to this. The child (a girl) had at birth a mark of bronze pigment resembling a fish with the head uppermost (photograph given) on the corresponding part of the same leg. Daughter's health good; throughout life she has had a strong craving for sunfish, which she has sometimes eaten till she has vomited from repletion. (C. F. Gardiner, Colorado Springs, American Journal Obstetrics, February, 1898.)
The next case occurred in a bitch. A thoroughbred fox terrier bitch strayed and was discovered a day or two later with her right foreleg broken. The limb was set under chloroform with the help of Röntgen rays, and the dog made a good recovery. Several weeks later she gave birth to a puppy with a right foreleg that was ill-developed and minus the paw. (J. Booth, Cork, British Medical Journal, September 16, 1899.)
Four months before the birth of her child a woman with four healthy children and no history of deformity in the family fell and cut her left wrist severely against a broken bowl; she had a great fright and shock. Her child, otherwise perfect, was born without left hand and wrist, the stump of arm terminating at lower end of radius and ulna. (G. Ainslie Johnston, Ambleside, British Medical Journal, April 18, 1903.)
The belief in the reality of the transference of strong mental or physical impressions on the mother into physical changes in the child she is bearing is very ancient and widespread. Most writers on the subject begin with the book of Genesis and the astute device of Jacob in influencing the color of his lambs by mental impressions on his ewes. But the belief exists among even more primitive people than the early Hebrews, and in all parts of the world.[[189]] Among the Greeks there is a trace of the belief in Hippocrates, the first of the world's great physicians, while Soranus, the most famous of ancient gynæcologists, states the matter in the most precise manner, with instances in proof. The belief continued to persist unquestioned throughout the Middle Ages. The first author who denied the influence of maternal impressions altogether appears to have been the famous anatomist, Realdus Columbus, who was a professor at Padua, Pisa, and Rome at the beginning of the sixteenth century. In the same century, however, another and not less famous Neapolitan, Della Porta, for the first time formulated a definite theory of maternal impressions. A little later, early in the seventeenth century, a philosophic physician at Padua, Fortunatus Licetus, took up an intermediate position which still finds, perhaps reasonably, a great many adherents. He recognized that a very frequent cause of malformation in the child is to be found in morbid antenatal conditions, but at the same time was not prepared to deny absolutely and in every case the influence of maternal impression on such conditions. Malebranche, the Platonic philosopher, allowed the greatest extension to the power of the maternal imagination. In the eighteenth century, however, the new spirit of free inquiry, of radical criticism, and unfettered logic, led to a sceptical attitude toward this ancient belief then flourishing vigorously.[[190]] In 1727, a few years after Malebranche's death, James Blondel, a physician of extreme acuteness, who had been born in Paris, was educated at Leyden, and practiced in London, published the first methodical and thorough attack on the doctrine of maternal impressions, The Strength of Imagination of Pregnant Women Examined, and exercised his great ability in ridiculing it. Haller, Roederer, and Sömmering followed in the steps of Blondel, and were either sceptical or hostile to the ancient belief. Blumenbach, however, admitted the influence of maternal impressions. Erasmus Darwin, as well as Goethe in his Wahlverwandtschaften, even accepted the influence of paternal impressions on the child. By the beginning of the nineteenth century the majority of physicians were inclined to relegate maternal impressions to the region of superstition. Yet the exceptions were of notable importance. Burdach, when all deductions were made, still found it necessary to retain the belief in maternal impressions, and Von Baer, the founder of embryology, also accepted it, supported by a case, occurring in his own sister, which he was able to investigate before the child's birth. L. W. T. Bischoff, also, while submitting the doctrine to acute criticism, found it impossible to reject maternal impressions absolutely, and he remarked that the number of adherents to the doctrine was showing a tendency to increase rather than diminish. Johannes Müller, the founder of modern physiology in Germany, declared himself against it, and his influence long prevailed; Valentin, Rudolf Wagner, and Emil du Bois-Reymond were on the same side. On the other hand various eminent gynæcologists—Litzmann, Roth, Hennig, etc.—have argued in favor of the reality of maternal impressions.[[191]]
The long conflict of opinion which has taken place over this opinion has still left the matter unsettled. The acutest critics of the ancient belief constantly conclude the discussion with an expression of doubt and uncertainty. Even if the majority of authorities are inclined to reject maternal impressions, the scientific eminence of those who accept them makes a decisive opinion difficult. The arguments against such influence are perfectly sound: (1) it is a primitive belief of unscientific origin; (2) it is impossible to conceive how such influence can operate since there is no nervous connection between mother and child; (3) comparatively few cases have been submitted to severe critical investigation; (4) it is absurd to ascribe developmental defects to influences which arise long after the fœtus had assumed its definite shape[[192]]; (5) in any case the phenomenon must be rare, for William Hunter could not find a coincidence between maternal impressions and fœtal marks through a period of several years, and Bischoff found no case in 11,000 deliveries. These statements embody the whole of the argument against maternal impressions, yet it is clear that they do not settle the matter. Edgar, in a manual of obstetrics which is widely regarded as a standard work, states that this is "yet a mooted question."[[193]] Ballantyne, again, in a discussion of this influence at the Edinburgh Obstetrical Society, summarizing the result of a year's inquiry, concluded that it is still "sub judice."[[194]] In a subsequent discussion of the question he has somewhat modified his opinion, and is inclined to deny that definite impressions on the pregnant woman's mind can cause similar defects in the fœtus; they are "accidental coincidences," but he adds that a few of the cases are difficult to explain away. At the same time he fully believes that prolonged and strongly marked mental states of the mother may affect the development of the fœtus in her uterus, causing vascular and nutritive disturbances, irregularities of development, and idiocy.[[195]]
Whether and in how far mental impressions on the mother can produce definite mental and emotional disposition in the child is a special aspect of the question to which scarcely any inquiry has been devoted. So distinguished a biologist as Mr. A. W. Wallace has, however, called attention to this point, bringing forward evidence on the question and emphasizing the need of further investigation. "Such transmission of mental influence," he remarks, "will hardly be held to be impossible or even very improbable," (A. W. Wallace, "Prenatal Influences on Character," Nature, August 24, 1893.)
It has already been pointed out that a large number of cases of fœtal deformities, supposed to be due to maternal impressions, cannot possibly be so caused because the impression took place at a period when the development of the fœtus must already have been decided. In this connection, however, it must be noted that Dabney has observed a relationship between the time of supposed mental impressions and the nature of the actual defect which is of considerable significance as an argument in favor of the influence of mental impressions. He tabulated 90 carefully reported cases from recent medical literature, and found that 21 of them were concerned with defects of structure of the lips and palate. In all but 2 of these 21 the defect was referred to an impression occurring within the first three months of pregnancy. This is an important point as showing that the assigned cause really falls within a period when a defect of development actually could produce the observed result, although the person reporting the cases was in many instances manifestly ignorant of the details of embryology and teratology. There was no such preponderance of early impressions among the defects of skin and hair which might well, so far as development is concerned, have been caused at a later period; here, in 7 out of 15 cases, it was distinctly stated that the impression was made later than the fourth month.[[196]]
It would seem, on the whole, that while the influence of maternal impressions in producing definite effects on the child within the womb has by no means been positively demonstrated, we are not entitled to reject it with any positive assurance. Even if we accept it, however, it must remain, for the present, an inexplicable fact; the modus operandi we can scarcely even guess at. General influences from the mother on the child we can easily conceive of as conveyed by the mother's blood; we can even suppose that the modified blood might act specifically on one particular kind of tissue. We can, again, as suggested by Féré, very well believe that the maternal emotions act upon the womb and produce various kinds and degrees of pressure on the child within, so that the apparently active movements of the fœtus may be really consecutive on unconscious maternal excitations.[[197]] We may also believe that, as suggested by John Thomson, there are slight incoördinations in utero, a kind of developmental neurosis, produced by some slight lack of harmony of whatever origin, and leading to the production of malformations.[[198]] We know, finally, that, as Féré and others have repeatedly demonstrated during recent years by experiments on chickens, etc., very subtle agents, even odors, may profoundly affect embryonic development and produce deformity. But how the mother's psychic disposition can, apart from heredity, affect specifically the physical conformation or even the psychic disposition of the child within her womb must remain for the present an insoluble mystery, even if we feel disposed to conclude that in some cases such action seems to be indicated.
In comprehending such a connection, however at present undemonstrated, it may well be borne in mind that the relationship of the mother to the child within her womb is of a uniquely intimate character. It is of interest in this connection to quote some remarks by an able psychologist, Dr. Henry Rutgers Marshall; the remarks are not less interesting for being brought forward without any connection with the question of maternal impressions: "It is true that, so far as we know, the nervous system of the embryo never has a direct connection with the nervous system of the mother: nevertheless, as there is a reciprocity of reaction between the physical body of the mother and its embryonic parasite, the relation of the embryonic nervous system to the nervous system of the mother is not very far removed from the relation of the pre-eminent part of the nervous system of a man to some minor nervous system within his body which is to a marked extent dissociated from the whole neural mass.