"Maternal impression" is accepted as a specific designation to signify the real or supposed influence of emotion and especially serious trouble, which may affect the mother's mind during pregnancy and be transferred to the child in utero, with the production of deformities or mother's marks. There used to be an almost superstitious belief in the power of the maternal impressions to influence unfavorably the child in utero. With the newer developments as to the influence of the subconscious and subliminal there might well occur in some minds an exaggeration of these ideas with the production of much mental suffering at least, if not of more serious results.

Maternal Impressions in Old Literature.—The belief in the influence of maternal impression on the child in utero is so strongly fixed that to most people it will seem paradoxical to question the whole subject. The evidence for it, however, is quite trivial, and none of it rises above the grade of what may be explained by coincidence. But there are many apparently insuperable difficulties, from the standpoint of our modern scientific knowledge, with regard to the whole subject. If we take up the medical books and the popular science, or rather pseudo-science, and the folk stories of a century ago we find overwhelming evidence for the belief in maternal impressions. More recent {462} literature has but few examples, and the more the details are studied the less is the evidence of any kind that the mother's mind influences her unborn child. There is really no more reason why a child should he marked within its mother's womb than that it should be marked while nursing at the breast if something should happen to the mother at that time. This latter effect strikes one at once as absurd; the former, as we shall see, is exactly of the same nature.

Many of the older stories of maternal impressions are reported on no better grounds than the vomiting of snakes and the like, even live mice, which used to be found in old-time medical literature. It is true that there was usually no such morbidity about the stories of maternal impressions, but men wanted to find some explanation for the problem of the occurrence of deformities and markings and the maternal impression idea seemed satisfactory and inviting by its very mystery. The belief that animals could live for some time in human stomachs is now relegated to the limbo of old-time credulous traditions. Maternal impressions are on the same path and in twenty-five years they will be as great curiosities in serious medical literature as the gastric fauna of two generations ago. Under these circumstances prospective mothers who are anxious over possibilities and who have dreads of all kinds about their unborn children should be reassured and informed as to the scientific status of this important question.

Mother and Child Distinct Beings.—There is no direct connection between the mother and her unborn babe. No nerves run in the cord and none pass from the uterine tissues to the placenta. It is easy to understand the influence of mind on body under ordinary circumstances, at least the mystery has a rational explanation. The central nervous system rules the nutrition of the body. To cut off the nerve supply has as serious an effect as to cut off the blood supply. Owing to the existence of a chain of neurons, that is, a succession of nervous elements, instead of one continuous nerve fiber from center to periphery, it is possible for one of the neurons of the chain to be so disturbed that the conducting apparatus is interrupted and impulses do not flow. Hence, if a strong impression is produced on the mind with regard to a particular part of the body the neurons leading to it may be so disturbed that trophic nerve impulses do not flow down, the blood supply of the part may be disturbed through the vaso-motor system and consequent changes may take place.

Absence of Circulatory Connection.—Since no nerves pass, as we have said, from mother to babe, disturbances acting on the mother's mind can at most only influence the blood supply to the baby. Most people think that there is a direct blood supply from mother to child and that the mother's blood literally flows in the baby's veins. This is not true. The baby's blood is an entirely independent structure, originating in the child's own body, and always maintaining a distinct and quite different composition from that of the mother. The baby's blood has a higher specific gravity, and it has, in normal condition, nearly double as many red corpuscles to the cubic millimeter as the mother's blood. If the blood supply is disturbed by mental influences, then it is not the baby's blood nor its circulation that is disturbed, but only the circulation through the maternal part of the placenta where an exchange of gases and nutrient elements between mother's and baby's blood takes place. It is {463} impossible to conceive that during this passage through a membrane of nutrient elements, soluble proteids, gases, etc., mental influences should also pass over.

Supposed Examples of Maternal Impression.—The stories that are told would lead us to believe that somehow definite changes in the mother are reproduced in the babe. One case, which in a circle of friends that I knew very well made many a convert to the idea of maternal impressions, was that of a young woman at whom, during an early stage of her first pregnancy, her husband playfully threw a tiny frog. He did not know that she had a mortal dread of frogs. She was seriously frightened and put up her hand to ward off the animal, and as the clammy thing struck her palm she felt a shiver go through her. When her baby was born a curious growth that had some pigment in it and that, by a stretch of the imagination, might be considered to resemble a frog was in the baby's hand—the same hand, by the way, as that which the mother used to ward off the animal. The lack of any nervous connection and of any direct blood connection between mother and child makes the story simply absurd as an illustration of maternal impression.

In recent years such stories have come from more and more distant parts of the country. Kansas was the principal source of them until a generation of great editors arose there. Texas was then their favorite location, but Texas has in recent years become so progressive and so closely connected with the rest of the world that, in spite of its size, it does not produce so many of these wonders. A generation ago the announcement of the birth of six children at once in Austria, or somewhere else in Central Europe, would usually be followed by a report from Texas announcing seven at a birth. Maternal impression stories grew luxuriantly for the benefit of the news-gatherer in dull seasons. A standing type of them is that of the farmer cutting hay on his farm who puts his fingers too far into the hay cutter and has them taken off. His wife binds up the bleeding stump. She is pregnant at the time. When her baby is born—usually two or three months later—just the same fingers are missing on the same hand of the child. Now the mechanism by which such maternal impression could be transferred to the child is incomprehensible. There is no connection between the two, and the old metaphysical axiom (actio in distans repugnat) that all action between bodies at a distance from one another, that is without some connecting link between them, is absurd, holds as good in modern times as it did in the Middle Ages. Surely a tendency-to-amputation is not carried over from mother's blood to baby's blood through the membrane in the placenta just as are the gases for respiration and the nutrient elements for food. If it is, we have a greater mystery than ever to solve.

Period of Occurrence.—The infant in the uterus is fully formed before the tenth week of pregnancy and at a time when women are usually almost unconscious of the fact that they are pregnant. Such impressional changes as we have referred to, if produced after this, must be in the nature of backward growth or an inversion of trophic influences or a great perversion of embryonic life. They have nothing to do with the formation of the child, since that is completed. They are as much accidents as if the child should fall after it was born. We know how fetal limbs are amputated through the formation of amniotic bands, but that maternal impressions should influence the formation of these bands is of itself ridiculously absurd. That it should {464} influence them in a directive and selective way so that certain limbs may be amputated at a certain point reaches a climax of absurdity. A distinguished physician of our generation once said that one might as well hope to absorb a pencil case in one's vest pocket by medicine as to try to bring about absorption of fully formed connective tissue by drugs. We cannot think of any mental influence bringing about such absorption, yet to credit maternal impressions with the production of fetal amputations not only supposes the directive formation of connective tissue within the uterus, quite beyond the domain of the influence of the mother's nervous system, but also assumes the direction of the anomalous action of that connective tissue in its mutilating procedures in a very exact and definite way.

Some curious things have been explained on the score of maternal impressions and it is this very exaggeration that is perhaps the best proof of how coincidence, imitation, and other factors play a role that has exaggerated the idea of maternal impressions into a causative factor. A typical illustration is the case cited years ago, half in joke, perhaps, half in earnest, by a distinguished professor of obstetrics. It occurred in the days when the elder Sothern was playing Lord Dundreary to crowded houses and when Dundrearyisms were the current witticisms and Dundreary ties and Dundreary clothes and Dundreary whiskers were all the rage. A young woman who was recently married became much taken with the actor and went to see him over and over again, secured an introduction to him, and showed the liveliest interest in him and the performance. Their acquaintance, however, remained merely that of chance friends. Some months after it began, not more than five or six at the most, a boy was born to her. According to the story this boy, when he began to walk some years later, developed that little skip in his gait which proved so taking to those who crowded the theaters to see Sothern as Lord Dundreary.

By this time the play had lost something of its vogue and most people did not recognize the curious halt in the gait, but it was very clear to the mother and her friends. It was set down as due to a maternal mental impression. Mental transfer seems ludicrous in this case. It is much more likely that the mother was hysterical, and, wishing in a morbid way to attract attention to herself and her child, taught the boy the little skip, or perhaps some curious little skip once taken by the child attracted the mother's attention because of her memory of Sothern, and her surprise at the act impressed the peculiar action upon the boy's mind, who proceeded to attract further attention by repeating it. It is cases like this with their reductio ad absurdum of the whole process that have quite discredited the belief in maternal impressions.

Some Figures and Coincidences.—The occurrence of mothers' marks in connection with various external incidents of pregnancy are only coincidences. Most young mothers dread lest something should happen to their children. About once in a thousand times an infant is marked in some way. Nine hundred mothers rejoice over the fact that their baby is not marked in spite of the fact that they feared it might be, ninety-nine of them never gave the matter any thought and one of them finds to her sorrow that her foreboding has come true. Occasionally a mother who has not dreaded such a result finds that her offspring is marked. Then she recalls all the happenings of her pregnancy and picks out something to which she thinks she may attribute the accident. {465} There must be some reason for it and she finds it. Sometimes she begins by saying that it must be because she was frightened at such a time, or fell down at such a place, or saw such a thing, and then a week later she tells the story with circumstantial additions which make it very clear to her friends that she knows exactly the reason and that she had thought about it before and feared it might be so, though the whole matter was hazy until it had been talked over a number of times.

Coincidences have been the most serious detriment in drawing scientific conclusions in every department of medicine. Most of our diseases are self-limited and any medicine that was given being followed by recovery seemed to be the cause of that recovery and the more strictly self-limited a disease the greater the number of remedies. When stories of maternal impressions are analyzed it is found that a great many mothers have had forebodings as to their children being marked and their dreads have not come true. A few have feared and have realized their worst fears. Many women whose children are marked can recall no event in the course of their pregnancy which could have marked their child and they ask the doctor what he thinks must have been the reason. But unintelligent mothers can always find some cause by searching out unpleasant details of their experience during pregnancy.

Intrauterine Nutrition and Nursing.—To explain the occurrence of a frog-like appearance or a mousey patch on a baby as due to its mother having been frightened by one of these little animals while nursing would be the height of absurdity. But it is no more absurd than the supposition that mental impressions in the late months of pregnancy can have the effects that are popularly ascribed to them. If a mother suffers from severe fright, or even if she has a fit of intense anger or other profound mental disturbance, her milk may disagree with her infant. Every physician has seen nursing infants made sick by the change in the milk superinduced by strong mental emotions in the mother. This, however, could have nothing to do with the production of a special lasting physical mark on the outside of the body.

Maternal Solicitude and Superstition.—The wonderful stories that are told are nearly all in the older literature and are much more reasonably explained on the score of coincidence than on that of any possible direct connection of cause and effect. Mothers, then, may be reassured and made to understand that the better their own health, the less they worry about their condition, the more likely is their pregnancy to terminate favorably with a perfectly healthy offspring. This is the source of so much concern in the little world of child-bearing that it is worth while taking it seriously and making mothers understand that the old notions in this matter are but superstitions. Superstitions are not always nor exclusively religious, they are survivals from a previous state of knowledge, the reasons for which are now known to be false. Maternal impression, that is, the belief in the power of the mother's mind over the unborn child, is a superstition that we must now dismiss.

Favorable Maternal Influences.—Every now and then a sensational newspaper has an article on how mothers will tend to make their children physically handsomer by gazing at beautiful works of art, beautiful scenes in nature, and seeing only handsome (one feels like inserting well-dressed in the category, also) people during pregnancy. The reading of good books {466} containing moral lessons of the highest quality are supposed to have something of the same influence on the child's character. There is no doubt at all that the more carefully and simply and beautifully and healthily the mother lives, and the more her mind possesses itself in peace and happiness, the better will be her own nutrition and consequently that of her offspring, and, all things considered, this will contribute to the perfection of the infant's body and so give the best instrument for the expression of its soul. That these supposed favorable influences have any more direct power than this over the state of the infant that is to be is doubtful. It is worth trying for, but if the indefinite influence for good emphasizes, as it apparently does in many minds, the presumed direct and definite influence for evil, then it is not worth dwelling on.

Etiology of Deformities.—But if these curious deformities and markings are not due to maternal impressions, what, then, is their cause? To the question for many of the minor marks and slight deformities—naevi vascular and pigmentary, extra fingers, slight overgrowths, special peculiarities of bone and soft tissues—no satisfactory answer can be given. We must simply say that as yet we do not know. It is a good thing to say we do not know. Long ago Roger Bacon declared that the principal reason why man did not advance in knowledge more in spite of the amount of their work was that they were afraid to say "I do not know," and accepted inadequate reasons and insufficient authority in order to avoid this humiliating expression. On the other hand, there are many deformities and markings, the reasons for which have been found, and the more important they are the more we know about them, as a rule. Besides, with the advance of our knowledge of embryology we are getting to know more and more about these difficult problems and many things that were mysteries before are now clear. In addition to observation we have experiment and this is making observation more thoroughly scientific.

The more we know of the intricacies of the development of animals and human beings, the greater is our surprise that deformities do not occur even more commonly than they do. All the openings of the human as of the animal body gradually close in with the production of the finished form. The slightest interference with growth in the neighborhood of these openings, which involve nearly all of the front of the body, leaves various deformities. Nature has surrounded the developing embryo with fluid so that it is saved from jars of all kinds and from contact with other tissues that would disturb growth. Cell is laid on cell as brick is laid on brick in the building of a house, and the predetermined plan in the immense majority of cases is followed without accident to the minutest detail. That more mishaps do not occur, considering the delicacy of the process and the perfection of the finished structure, is hard to understand.

There are many factors likely to intrude in every pregnancy that may lead to the production of unfortunate results. Literally millions of cells are growing with apparent freedom from constraint in many portions of the fetus, yet all are directed with definite purpose corresponding to other cells and are destined to meet in due course of time. Each one of them or at least each group seems to be independent in its growth. Each growing cell doubles by dividing every few hours, yet all are co-ordinated to a definite end. We admire the men who begin at the two ends of a tunnel far distant from one another and work without any communication except through the engineer's plans {467} made long before, and yet make two bores that can be depended on to meet with but a few inches of divergence. The bridges of tissue that are built across the openings of the body jut out to meet one another in this way and in more than ninety-nine out of every one hundred cases there is not the slightest divergence. Many things may occur to disturb conditions—not connected with mental influences, but with distinctly physical factors—missteps, trips, jars on stairs or getting off and on cars, on the sidewalk, etc. These, and not the mythical factors that make up so-called maternal impressions, are the causes of deformities and mothers' marks.{468}