Private Sex Advice to Women: For Young Wives and those who Expect to be Married

by Robert B. Armitage

"Quite generally, then, there are two conceivable methods by which the sex might be artificially influenced in any particular case; firstly, if means could be found of ensuring that any particular fertilized ovum received the required chromosomes; and, secondly, by the discovery of methods which always effect the ovum or embryo in such a way as to produce the desired sex. Many suggestions for applying both methods have been made, some of which have attained considerable notoriety, but hitherto none of them has stood the test of practical experience. In the case of the higher animals, especially of the mammals, in which the embryo develops in the maternal uterus until long after the sex is irrevocably decided, it is obviously difficult to apply methods which might influence the sex after fertilization, even if it were certainly known that such methods were ever really effective.

"Apart from the few experiments like those of Hertwig on rearing tadpoles at different temperatures, there have been a very few cases in which there is even a suggestion that the sex of the fertilized egg can be modified by environment, and the belief that this is possible has been entirely abandoned by many of the leading investigators of the subject. It is probable, therefore, that if it will ever be possible to predict or determine artificially the sex of a particular child, the means will have to be sought in some method of influencing the output of germ-cells in such a way that one kind is produced rather than the other. It is in this way that Heape and others interpret the results of their investigations; they find that certain conditions affect the sex-ratio of cells, and they explain the result by assuming that under some circumstances male-determining ova are produced in excess, and under other circumstances, female-determining."

Professor Rumley Dawson holds to the opinion that the male-determining and female-determining ova are discharged alternately from the ovaries. In woman one ovum is usually discharged each month, and it is maintained that on one month the ovum is male-determining, and in the next, female-determining. It is obvious that exceptions must occur, for boy and girl twins are quite common, but if the cases which support the hypothesis are taken by themselves, and the exceptions explained away, it is possible to make out a strong case in favor of this theory. Some authorities hold that the right ovary produces male-determining ova, and the left ovary female-determining, and that the two ovaries discharge an ovum alternately, but an impartial examination of the evidence for this belief shows that it rests on very slender foundations. Experiments on the lower animals have shown that after the complete removal of one ovary the female may produce young of both sexes. Women, also, have produced children of a particular sex after the corresponding ovary has been removed, and it is hardly possible to believe that the removal in all these cases was incomplete. On the whole it must be concluded that the theory is insufficiently supported by the evidence.

Another widely promulgated and vigorously supported theory is that which holds that the sex of the future child may be determined by specific nutrition of the mother before conception, and in some cases after conception. Schenk's theory, advanced about 1900, attracted much attention at the time. He based his method on the observation that a number of women whose children were all girls all excreted sugar in their urine, such as happens in the case of persons affected with diabetes. From this he suspected that the physiological condition which leads to the excretion of sugar was inimical to the development of male-determining ova, and that males could be produced by its prevention. He therefore recommended that those who desire a male child should undergo treatment similar to that prescribed for diabetes for two or three months before conception, and held that a boy would be produced by these methods. Although this method has had considerable vogue, it cannot be held to have been established on a scientific basis.

Doncaster says "The general conclusion with regard to man must therefore be that if sex is determined solely by the spermatozoon there is no hope either of influencing or predicting it in special cases. On the other hand, there is considerable evidence that the ovum has some share in the effect, and if this is so, before any practical results are reached it will be necessary to discover which of two conceivable causes of sex-determination is the true one. It is possible that there are two kinds of ova, as well as two kinds of spermatozoa, and that there is a selective fertilization of such a kind that one kind of spermatozoon only fertilizes one kind of ovum, the second kind of spermatozoon the second kind of ovum. If this should prove to be the case, it is possible that means might be found of influencing or predicting that kind of ovum which is discharged under any set of conditions. Secondly, it is possible that the ova are potentially all alike, but that their physiological condition may under some circumstances be so altered that the sex is determined independently of the spermatozoon. * * * It is hardly possible to avoid the conclusion that the sex of the offspring may be influenced, at least under certain circumstances, by the mother. The search for means of influencing the sex of the offspring through the mother is not of necessity doomed to failure. No results of a really positive kind have been obtained hitherto, and some of the facts point so clearly to sex-determination by the male germ-cell alone in man and other animals that many investigators have concluded that the quest is hopeless; but until an adequate explanation has been given of certain phenomena discovered in the investigation of the subject, it seems more reasonable to maintain an open mind, and to regard the control of sex in man as an achievement not entirely impossible of realization."

Another writer on the subject has said: "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 this stage, the embryo is susceptible of being influenced by external conditions to develop more strongly in the one or the other direction and thus become distinctly and permanently male or female. It is evident that this is the season in the development of the individual in which influencing conditions and causes must operate in deciding its sex, although it is possible in some of the lower animals to alter the tendency of sex in the embryo from one sex to the other, even after it has been quite definitely determined. It is well established, in fact, that differences do not come from a difference in the ova themselves; that is, there is not one kind of ova from the female which becomes female, while other ova become male, for it is possible to alter the tendency toward the one sex or the other after the ovum has been fertilized and the embryo has begun its career of development. This possible change in sex tendency in the embryo also proves that sex is not decided by a difference in the spermatozoa; that is some of the sperm cells from the father are not male, while others are female, in their constitution.

"It is incorrect to suppose, as has been held by some theorists, that one testicle give rise to male spermatozoa and the other to female spermatozoa, for both male and female offspring have been produced from the same male parent after one testicle or the other has been removed. The same is true in cases in which either ovary has been removed from the mother; that is, male and female offspring are produced from mothers in whom either ovary has been removed. In like manner, the sex of offspring is shown not to be materially affected by the comparative vigor of the parents; thus, a stronger father than mother does not necessarily produce one sex to the exclusion of the other. These negative decisions are important because they simplify the solution of the problem of sex-determination, by excluding, more or less fully, various causes which have been supposed to operate quite forcibly in deciding the sex of offspring. Some of the more positive agencies that enter into the determination of sex are found (1) in the influence of nutrition upon the embryo during its indifferent stage of sexual development, and (2) in the constitution and general condition of the mother before and during the early stages of pregnancy. These two factors appear to enter more fully than any others in the decision of the sex in offspring, and deserve the greatest consideration. The influence of food in supplying the embryo with nourishment for its development is, perhaps, the most potent of these determining causes."

Investigators along the line of theory indicated in the above last quotation, i. e., the theory of sex determination by means of nourishment of the mother and embryo, have presented a volume of reports which demand respectful consideration. The general report may be said to be the discovery that abundant nourishment during the period of sexual neutrality tends to produce females; while lack of abundant nutrition during such period tends to produce males.

These experiments, of course, have been chiefly performed upon the lower animals. The frog has been a favorite subject of such experiments—the tadpole stage being the one selected, because in that stage there exists a lack of sex, the stage being one of sex neutrality. Professor Yung's celebrated experiments will illustrate this class of experiments. Here were chosen 300 tadpoles, which when left to themselves manifested a ratio of 57 prospective females to 43 prospective males. These were divided into three classes of 100 tadpoles each. Each class was then fed upon one of several kinds of nutritious diet in order to ascertain the change in sex-tendency due to such food. The first set, with an original ratio of femaleness of 54 to 46, were fed abundantly on beef, and the ratio of femaleness was changed to 78 to 22. The second class, with a ratio of femaleness of 61 to 39, were fed on fish (specially nourishing to frogs), and the ratio changed to 81 to 19. The third class, with a ratio of 56 to 44, were fed upon a still more nutritious diet (i. e., that of frogs' flesh), and the ratio was raised to 92 to 8. In short, the experiments showed that the increase of nourishment in diet changed every two out of three male-tendency tadpoles into females. The experiment was held to prove that a rich diet, affording nourishment, during the period of sexual neutrality in the embryo, tended to develop femaleness.