Artificial insemination

“ Where the injection is undertaken by a woman doctor, the husband need have no feeling that his wife has been violated. And while it is not certain that this method would succeed in giving the child she longs for to the woman, yet there are sufficient records in the medical profession of successful artificial insemination for it to offer much hope to a pair who have been denied perfectly normal parenthood either through the husband's actual sterility or the lack of mutual adjustment in their organs, or from an ill-understood lack of chemical affinity. ”

“ It was to save the young embryos from exposure to these and kindred dangers that I, as a volunteer employee of the United [Pg 235] States Fish Commission during the summers of 1897 and 1898, among other things resorted to the artificial fertilization of the eggs in a temporary laboratory, carrying the delicate embryos to the swimming stage and dumping them by thousands into the bay. ”

“ When sterility is due to a defect in the husband's spermatozoa, and is not discovered, as it usually might be, before marriage, the question of impregnating the wife by other methods has occasionally arisen. Divorce on the ground of sterility is not possible, and, even if it were, the couple, although they wish to have a child, have not usually any wish to separate. Under these circumstances, in order to secure the desired end, without departing from widely accepted rules of morality, the attempt is occasionally made to effect artificial fecundation by injecting the semen from a healthy male. ”

“ In a case which a priori seemed exceedingly well adapted for the performance of artificial fertilization, one of marked hypospadias in a man whose semen was abundant and contained a large number of vigorously moving spermatozoa, I saw this experiment fail, in spite of all possible care in its performance. In fact, not a single conclusive instance of successful artificial fertilization in the human species is known to me, though I have seen reports of numerous 320disagreeable and even dangerous results of attempts to effect it. ”

“ It may be proper to attempt the artificial fecundation of a virgin queen, by introducing a little of the male's prolific fluid with a pencil, and at the same time observing every precaution to avoid error. Artificial fecundation, you are aware, has already succeeded in more than one animal. ”

“ The nozzle of the syringe was then carefully introduced into the cervical canal, and half a drop of semen was slowly injected into the uterine cavity. For two or three hours after the operation, the patient remained lying quiet in bed. After the tenth experiment, conception ensued—the first recorded case of artificial fertilization in the human species. ”

“ Artificial parthenogenesis designates the development of unfertilized ova which normally would not develop at all and which are stimulated to development by placing them under artificial chemical conditions. Doubtless many of you have seen in the newspapers these experiments referred to as if they gave the actual creation of life. Of course that is nonsense. The life is there in the ovum. What artificial parthenogenesis accomplishes is to supply a stimulus, chemical in nature and capable of replacing the fertilization by the spermatozoon, which would otherwise be necessary. ”

“ It has never been the object of breeders or of horticulturists to select variations in the direction of cross-infertility, for the swamping effects of intercrossing are much more easily and rapidly prevented by artificial isolation. ”

“ Artificial Impregnation.—It may not be generally known that union is not essential to impregnation; it is possible for conception to occur without congress. All that is necessary is that seminal animalcules enter the womb and unite there with the egg or ovum. It is not essential that the semen be introduced through the medium of the male organ, as it has been demonstrated repeatedly that by means of a syringe and freshly obtained and healthy semen, impregnation can be made to follow by its careful introduction. ”

“ This might be done by what is known as "selective fertilization" artificially with only the kind of sperm (X or Y as to chromosomes) which would produce the desired result. There is as yet no way to thus select the sperm of higher animals. It has been authoritatively claimed that feeding with certain chemicals, and other methods to be discussed later, has affected the sex of offspring. These experiments (and controversies) need not detain us, since they are not applicable to the human species. ”

“ Most commonly used ARTs rely on fertilization as a first step. This joining of egg and sperm is accompanied by the recombination of the genetic material from the sire and dam, and is often referred to as "shuffling the genetic deck." ”

“ In the old days of unlimited fecundity, the early marriage of a beautiful, or intelligent, woman meant a probable perpetuation of her endowments; but at present, when artificial restraint of fertility is so widespread, the result does not follow as a matter of course: and it is evident that the race is little or not at all helped by the early marriage of an attractive woman, if she has too few or no children.
Fecundal selection, then, is becoming the important phase of reproductive selection, in the evolution of civilized races. ”

“ It may, however, well be that the capacity for wintering in the dry state has physiologically replaced the need for resistant fertilized eggs. Insemination takes place either by the introduction of the penis into the cloaca of the female, or by the puncture of the bodywall of the female by the penis, and the injection of the sperm into the body cavity, whence the single spermatozoa must make their way to the eggs. The females habitually produce eggs without impregnation, which again habitually develop into females, more rarely into males. ”

“ From a breeder’s perspective, phenotypes resulting from sexual reproduction cannot be predicted—that is, the characteristics of the offspring from a mating may be estimated, but not predicted with certainty. Nuclear transfer, the most advanced of these technologies, does not require fertilization and allows for the propagation of known genotypes and phenotypes without the risk of genetic reshuffling. ”

“ Jacobi had, however, practiced artificial fecundation in animals (in 1700) and John Hunter in man. See Gould and Pyle, Anomalies and Curiosities of Medicine, p. 43; also Janke (Die Willkürliche Hervorbringen des Geschlechts, pp. 230 et seq.) who discusses the question of artificial fecundation and brings together a mass of data. ”

“ It should be realised that all the proper, medical methods of controlling pregnancy consist, not in destroying an already growing embryo, but in preventing the male sperm from reaching the unfertilised egg cell. This may be done either by shutting the sperms away from the opening of the womb, or by securing the death of all (instead of the natural death of all but one) of the two to six hundred million sperms which enter the woman. ”

“ Fecundal selection is said by them to be constantly tending to increase the reproductive rate, because fecundity is partly a matter of heredity, and the fecund parents leave more offspring with the same characteristic. Lethal selection, on the contrary, constantly asserts its power to reduce the reproductive rate, because the reproductive demands on the parents reduce their chances of life by interference with their natural ability of self-protection. ”

“ Artificial impregnation is a very valuable process, for, by its aid, every stage in development may be obtained. Eggs and milt may be mixed under the microscope, and all the phenomena of the maturation of the egg and its impregnation can then be followed as well as the processes of segmentation which result in the conversion of the single-celled egg into the many-celled embryo. ”

“ For the purposes of the definition of "human embryo clone" in subsection (1) , a human embryo that results from the technological process known as embryo splitting shall not be taken to be created by a process of fertilisation of a human egg by human sperm. ”

“ The facts of Artificial Parthenogenesis, as the chemical fertilisation of the egg is called, have, perhaps, some bearing on the problem of evolution. If we wish to form a mental image of the process of evolution we have to reckon with the possibility that parthenogenetic propagation may have preceded sexual reproduction. This suggests also the possibility that at that period outside forces may have supplied the conditions for the development of the egg which at present the spermatozoon has to supply. ”

“ I believe the time now is right and the time is ripe for the Congress of the United States to act, and that is why I have introduced legislation today that would make human reproductive cloning, as well as embryonic cloning, illegal in the United States of America. ”

“ Hence the smaller the chances of any single sperm-cell being successful, the larger is the number of such cells produced, and a direct result of this increase in number is a diminution in size. But why should the sperm-cells remain or become so large in the species in which fertilization is internal? The idea suggests itself that the species in this way gains some advantage, which must be given up in the other cases; although such advantage might consist in assisting the development of the fertilized ovum and not in any increase of the true fertilizing substance. ”

“ It thus appears that, in such a case as here supposed, natural selection would preserve those portions of the two breeds which were most infertile with each other, or whose hybrid offspring were most infertile; and would, therefore, if variations in fertility continued to arise, tend to increase that infertility. ”

“ On the whole, then, it appears clear that no form of infertility or sterility between the individuals of a species, can be increased by natural selection unless correlated with some useful variation, while all infertility not so correlated has a constant tendency to effect its own elimination. But the opposite property, fertility, is of vital importance to every species, and gives the offspring of the individuals which possess it, in consequence of their superior numbers, a greater chance of survival in the battle of life. ”

“ But none of these objections would have much weight if it could be clearly shown that natural selection is able to increase the infertility variations of incipient species, as it is certainly able to increase and develop all useful variations of form, structure, instincts, or habits. Ample causes of infertility have been shown to exist, in the nature of the organism and the laws of correlation; the agency of natural selection is only needed to accumulate the effects produced by these causes, and to render their final results more uniform and more in accordance with the facts that exist. ”

“ It is by no means necessary that all varieties should exhibit incipient infertility, but only, some varieties; for we know that, of the innumerable varieties that occur but few become developed into distinct species, and it may be that the absence of infertility, to obviate the effects of intercrossing, is one of the usual causes of their failure. All I have attempted to show is, that when incipient infertility does occur in correlation with other varietal differences, that infertility can be, and in fact must be, increased by natural selection ”

“ But if it may be assumed that human twins, when identical, have been derived from a single egg, it seems to me to be extremely probable that fertilization was also effected by a single sperm-cell. We cannot understand how such a high degree of similarity could have been produced if two sperm-cells had been made use of, for we are compelled to assume that two such cells would very rarely contain identical germ-plasms. ”

“ While the evidence at our command regarding the artificial production of mutations is not yet sufficiently exact and trustworthy to enable us to draw definite conclusions and formulate recommendations for practical breeders, it may be stated that this is apparently one of the most profitable lines of experimentation for the immediate future. ”

“ It appears as if fertility depended on such a delicate adjustment of the male and female elements to each other, that, unless constantly kept up by the preservation of the most fertile individuals, sterility is always liable to arise. This preservation always occurs within the limits of each species, both because fertility is of the highest importance to the continuance of the race, and also because sterility (and to a less extent infertility) is self-destructive as well as injurious to the species. ”

“ We must not lose sight of the fact, in the midst of these various and diverging observations about the fertilization of the ova of one species by sperms of another species, that there is such a thing as "parthenogenesis," or virgin-birth. In some of the insects and lower forms of animals the egg-cell habitually and regularly develops and gives rise to a new individual without being fertilized at all. ”

“ So long therefore as a species remains undivided, and in occupation of a continuous area, its fertility is kept up by natural selection; but the moment it becomes separated, either by geographical or selective isolation, or by diversity of station or of habits, then, while each portion must be kept fertile inter se, there is nothing to prevent infertility arising between the two separated portions. ”

“ It has elsewhere been shewn by me (ibid. vol. ii. p. 185, and ‘Origin of Species,’ 5th edit. p. 317) that the sterility of crossed species has not been acquired through natural selection: we can see that when two forms have already been rendered very sterile, it is scarcely possible that their sterility should be augmented by the preservation or survival of the more and more sterile individuals; for as the sterility increases fewer and fewer offspring will be produced from which to breed, and at last only single individuals will be produced, at the rarest intervals. ”