Impregnation

“ Although the ovum which is destined to be fertilized is surrounded by several spermatozoa, only one actually enters and fuses with it.
This fusion is termed impregnation, fertilization, or, in lay parlance, conception, and the instant at which it occurs marks the beginning of pregnancy. The establishment of this fact is of no little importance, since it does away with any possible controversy concerning the time at which a new life begins. The origin of the child is exactly coincident with the fusion of the male and female germinal cells. ”

“ If we examine the fertilized germ, we discover unusual activity, the result of impregnation. Organic processes succeed one another with wonderful regularity, as if wrought out by inexplicable intelligence. Here begin the functions which constitute human physiology.
Generation requires that a spermatozoön be brought into actual contact with a germ that fecundation may follow. ”

“ A learned lecturer on medical jurisprudence gives it as his opinion, that the smallest quantity of seminal discharge, deposited in the lower part of the female generative apparatus, provided the female be apt to conceive, is sufficient for impregnation: and it is astonishing how minute a quantity of this plastic agent is necessary for that purpose in some species of creatures. ”

“ This process is brought about, as we all know, by the sexual intercourse of the two sexes, and is called the act of impregnation. The result of this act on the part of the male and female is, that the formation of a new being is set up in the ovule or egg; this ovule or egg soon begins to be divided and subdivided, and to be fashioned into various complex organisms, and eventually to develop into the form of one of its parents, as I explained in the first lecture. These are the processes by which the perpetuation of organic beings is secured. ”

“ There are many who manifest a laudable desire to understand the physiology of conception, the changes which take place, and the order of their natural occurrence. When impregnation takes place at the ovaries or within the Fallopian tubes, there is exuded upon the inner surface of the womb a peculiar nutritious substance. It flows out of the minute porous openings surrounding the termination of the Fallopian tube within [pg 216] the uterine cavity, and, thus, is in readiness to receive the germ, and retain it there until it becomes attached. ”

“ Abortion is the expulsion of an ovum the product of a conception, and can only occur during the period of menstrual life, as conception, the impregnation of the female ovule by the male semen, is the consequence of fruitful intercourse, liable to take place at any time during the period of womanhood, the thirty years of female menstrual life from puberty—the appearance of the catamenia—to the time of their cessation. ”

“ Of the enormous number of ova existing in each woman, relatively few mature and it is apparent that still fewer are fertilized, since each impregnation results in an abortion, a premature labor or a full term child. ”

“ The first impregnation of the egg, whether in man or in kangaroo, is the birth of the offspring to life; its emergence into the outside world for wholly separate existence is, for one as for the other, but an accident in time. It has been asserted by some authors, as by Meigs, that conception is only coincident with the attachment of the impregnated egg to the uterine cavity for its temporary abode therein, or, in exceptional cases, as in extra-uterine pregnancy so called, with its attachment to some other tissue of the mother ”

“ Pregnancy a period of continence.—When impregnation occurs and the womb becomes the closed home of embryonic life, sexual desire largely or entirely{533} ceases in the normal woman. She now enters a nine-month period of gestation. Again it is natural for her to repel sexual approaches of her husband. All the pregnant females among the lower animals and savage man faithfully repel the approach of their mates during gestation. This law is violated alone by semi-civilized and civilized man. ”

“ Some physiologists have attempted to account for these remarkable results from a first impregnation by the close attachment and freely intercommunicating blood-vessels between the modified embryo and the mother. But it is a most improbable hypothesis that the mere blood of one individual should affect the reproductive organs of another individual in such a manner as to modify the subsequent offspring. ”

“ For if we suppose, as the immediate effect of impregnation, a swelling of the ovulum without a corresponding enlargement of the ovarium, the consequence will obviously be a premature rupture of the ovarium, and the production of a seed provided with its proper integuments only. ”

“ Before this egg has left the woman's ovary, before impregnation has been effected, it may perhaps be considered as a part and parcel of herself, but not afterwards. When it has reached the womb, that nest provided for the little one by kindly nature, it has assumed a separate and independent existence, though still dependent upon the mother for subsistence. ”

“ In accordance with the facts above given, which prove that in many cases a close relation exists between variability and the sterility following from changed conditions, we may conclude that the exciting cause often acts at the earliest possible period, namely, on the sexual elements, before impregnation has taken place. ”

“ I believe that after fecundation has been delayed for about three weeks, the mouth of the spermatheca becomes permanently closed, so that impregnation can no longer be effected; just as the parts of a flower, after a certain time, wither and shut up, and the plant is incapable of fructification. The fertile drone-laying workers, are in my opinion, physically incapable of being impregnated. ”

“ Here it may be met by the male life element, and if so, it becomes fertilized and remains in the uterus to grow into a baby. This is called fertilization, fecundation, impregnation or conception. But if the egg is not fertilized, [Pg 12] it passes from the uterus through the vagina and out of the body. The ovaries take turns in developing the ovum.
Every twenty-eight days or so a woman, from the time she is about thirteen or fourteen till she is about fifty, has a slight flow of blood from the uterus, which is called menstruation. ”

“ Although, in the last resort, fertilization depends on impulses attracting the spermatozoa to the ova, probably chemical in their nature, the necessary proximity is secured in a number of ways. In many simple cases the ripe products are discharged directly into the surrounding water, and impregnation is a matter of accident highly probable because such animals discharge enormous quantities of ova and spermatozoa, are frequently sessile and live in colonies, and are mature about the same time. ”

“ The offspring has 39been reduced in number, and the primitive uncertainty of impregnation has been replaced by a quite assured impregnation, and a more effective protection of offspring. The energy required for the production of eggs and sperma has been transferred into the creation of mechanisms of attraction, and mechanisms for the protection of offspring. ”

“ The uncertainty becomes still greater owing to our inadequate knowledge as to the length of time during which the sexual elements, the ova and the spermatozoa, retain their vitality after liberation from their respective sources. While it is not certainly known, it is probable that the ovum is capable of impregnation any time during its sojourn within the oviduct and before reaching the uterus, or probably for a period of about one week from the time of its escape from the Graafian follicle. ”

“ When intercourse takes place, if no preventive is employed, the semen is deposited in the woman's vagina. The ovule is not in the vagina, but is in the womb, farther up, or perhaps in the tube on its way to the womb. As steel is attracted to the magnet, the sperm of the male starts on its way to seek the ovum. Several of these sperm cells start, but only one enters the ovum and is absorbed into it. This process is called fertilization, conception or impregnation. ”

“ It is not always that the most healthy women are more favorable to conception than the spare and feeble. High feeding and starvation are alike occasionally inimical to breeding. The regularity of the “courses” appears principally essential to secure impregnation ”

“ This life-form, thus started, grows according to the laws of its becoming more and more, until, at the expiration of a fixed period, which varies greatly in different animals, it becomes a complete young individual, of the nature and kind of its parents. The fertilization of the ovum in the female is called conception; its growing state is called gestation, and its birth, on becoming a separate being, is called parturition. In its growing condition, and before its birth, the new young life form is known as the foetus. ”

“ The action of the cilia, under the stimulus of the sperm, seems to be from without, inward. Even if a minute particle of sperm, less than a drop, be left upon the margin of the external genitals of the female, it is sufficient in amount to impregnate, and can be carried, by help of these cilia, to the ovaries.
6. CONCEPTION.—After intercourse at the proper time the liability to conception is very great. If the organs are in a healthy condition, conception must necessarily follow, and no amount of prudence and the most rigid precautions often fail to prevent pregnancy. ”

“ EARLY DEVELOPMENT Some twelve days after conception, the female ovule or egg, which has been impregnated by the male spermatazoön, escapes from the ovary where it was impregnated, and entering a tube (Fallopian) gradually descends by means of it into the cavity of the womb or uterus. Here the little germ begins to mature in order to develop into an exact counterpart of its parents. In the human being the womb has only a single cavity, and usually develops but a single embryo. ”

“ The influences in the personality of the father and of the mother, which during fertilization find expression in the qualitative constitution of the sperm and of the ovum, respectively, can thus bring about a resultant tendency, acting in one direction or the other with varying force. Thus, after fertilization, we have this resultant tendency toward the formation of a male or female embryo.
But, Düsing continues, at this time the sex is not definitely determined. The influence of the nutritive condition in which the fertilized ovum finds itself has yet to make itself felt. ”

“ In this way, it is made sure that some of them will travel up through the uterus and oviducts, arriving in the neighborhood of the ovaries.
FERTILIZATION.—Convincing observations upon the lower forms of life, especially upon fishes, have shown that when the germinal cells come near to each other, the ovum attracts the spermatozoon. The power of attraction which the ovum exerts may be likened, most simply, to the influence of a magnet upon iron-filings. While there has been no opportunity to observe such attraction between the parent cells of human beings, its existence is not open to doubt. ”

“ Every individual among the higher animals, whether male or female, begins as an impregnated ovum in the mother's body. Any such ovum contains elements of constitution from both of its parents. In the earliest existence of this impregnated ovum, there is a season of sexual indifference, or indecision, in which the embryo is both male and female, having the characteristic rudiments of each sex, only indifferently manifested. ”

“ In a given mating, we must take into consideration such factors as impediments to coitus, as well as those numerous agencies in the female which may interfere with the union of sperm and ovum, or with the successful implantation of the fertilized egg in the uterus, and its growth and development there till normal parturition takes place. Successful reproduction depends upon the mating of sexually sound females to equally sound males. ”

“ At a later period, indeed, when the embryo is larger, when the ovum or conception has contracted adhesions with the uterus, and the umbilical vessels have penetrated the caruncles, the chorion extends further, and at its extremities on either side, and as it were in a couple of appendices, there is a certain fluid of a yellow colour, which you might call excrementitious, kept separate and distinct.
The human conception scarcely differs in any respect from an egg during the first months of pregnancy. ”

“ The stimulus of the sperm so pent up causes that ovary to mature a germ, although it may do so slowly, and after two or three months it is perfected, fertilized, and a second conception occurs within the uterus. If each embryo observe a regular period of growth and each be born at maturity, there must be an interval of two or three months between their births. But it is far more common for the parturition of the first, displaying signs of full maturity, to coincide with the birth of a second which is immature and which cannot sustain respiratory life. ”

“ In these cases the fœtus is found outside of the Womb, in the Tube, or the Ovary, or even in the Abdomen, among the intestines. Such an occurrence seems to render it almost certain that the ovum must have been fecundated in the Ovary, because we cannot well conceive, if it were not so, how it could reach the outside of the Womb. This difficulty is not, however, regarded as insuperable, by the advocates of the opposite theory. Possibly conception may occur in both ways.
There are many causes which prevent conception, or, in other words, which produce barrenness and [56] sterility. ”