Relationship between blood groups and sex ratio of the newborn.

The examinations prove that due to the foetomaternal blood group incompatibility the sex ratio of the newborn will be higher. The most probable explanation for this fact is that the foetomaternal blood group incompatibility exerts a negative effect on the X chromosome, in consequence of which the elimination rate of the zygotes fertilized by Y chromosome-carrying spermia decrease and thus the sex ratio will be higher. The highest sex ratio was found among the D-negative newborns of D-positive mothers (172.7), whereas the lowest one among the D-positive children of D-positive mothers (113.5). The incompatibility existing in the other antigens of Rh-system and in the ABO-system also elevated the sex ratio to a minor degree.

[The circumstances and background of the discovery of the Rh-factors]. / Az Rh-vércsoportok felfedezésének körulményei es háttere.

We can hardly meet references in the literature to the various circumstances and factors that played an important role in scientific discoveries, although interesting conclusions could be driven from them. So, e.g., in the case of Landsteiner it is sure, that his idea, to investigate the reason of the mechanism and of the formation of a phenomenon, came from the phenomenon itself: namely, from the agglutination called forth by the fortuitous mixing of the cadavers' blood in the dissecting room. The present paper deals with certain circumstances that played a role in the discovery of the Rh-Factors, resulting not only scientific, but practical consequences as well. The data used here were collected primarily from the memoirs of professors Wiener, Levine, Dahr and from those of Speiser (Vienna). The authors were helped in their research also by their personal contact with professor Dahr (Cologne) established in the sixties. Landsteiner was compelled to emigrate from Austria mainly by the vivid anti-Semitism of the early 20s. Supposedly, without his emigration the Rh Factors would have been discovered much later. Working in the Rockefeller Institute (New York) Landsteiner was provided with everything that was needed for his research. He had organised a team and, helped by his colleagues, he succeeded to open a new field in immunserology. Unfortunately, before he could have completed his scientific project, he had died--already as a Nobel-Prize winner--in 1943. His project was resumed by his colleagues. The method of Rh-examination, exceeding the field of medicine, quickly won a greater significance, in anthropology, genetics and in biology. It is worth to mention, that Landsteiner, had already indicated shortly after his discovery the fields, on which the Rh-examinations later played a significant role.

[Data and comments on the general validity of the weight limit of 2500 g for low-birth-weight infants]. / Angaben und Bemerkungen über die allgemeine Gültigkeit der Gewichtsgrenze von 2500 g für untergewichtige Neugeborene.

The authors describe the role of maternal body weight, duration of pregnancy and sex of newborn in the intrauterine growth of the fetus, more exactly in the development of birth weight. In this context they dealt with the validity of the 2500 g upper limit of low-birth-weight-infants in ethnically different populations. From the findings of their studies they draw the conclusion that the weight limit of 2500 g cannot be regarded as valid for all the populations at the statement of the proportion of low-weight births. In the authors view the question of the upper limit of low-weight newborns should be revised. At the statement of the weight limit a differentiation is necessary taking into consideration the constitutional difference in the populations as well as the average birth weight of the newborn and the sex. Authors find it permissible to use the weight value of 2500 g in comparative studies only in case of some populations with identical constitutional characteristics.

[Collection of obstetrical data in international cooperation]. / Geburtshilfliche Datensammlung in internationaler Zusammenarbeit.

Authors deal with the question of collecting obstetrical data within the framework of international co-operation. They mention that data collecting by individual obstetrical institutes is not suitable for getting reliable data on the degree of development of major geographical regions or countries in the field of obstetrical provision. Instead of this the authors suggest to acquire obstetrical-geographic data of central statistical institutes of the individual countries and to evaluate them in a centralized way.