A manual of midwifery : including the pregnancy and the puerperal state / by Karl Schroeder ; translated into English from the third German edition by Charles H. Carter.

Schroeder, Karl Ludwig Ernst, 1838-1887.

Date:: 1873

Credit: A manual of midwifery : including the pregnancy and the puerperal state / by Karl Schroeder ; translated into English from the third German edition by Charles H. Carter. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

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$refer the reader for that purpose to tlie historical pari of a paper by Cohnstein (' M. F. G.,' B. 31, p. 141). We shall only mention that in recent times two opinions have especially been contended for. The one, suggested by Aristotle, tries to explain the position of the foetus by means of the laws of gravity; the other, supported by Simpson with a great deal of ingenuity, says that the foetus makes reflex movements as long as it is in an uncomfortable position. Its most comfortable position, if its shape be compared with thai <»f the uterus, is with the head downwards. If it is not in this position a greater pressure is exerted on it by the uterine walls. This pres- sure causes reflex movements, and they continue until the most comfortable position — head presentation — is found. Others (Crede, Kristeller) thought the head position was dependent upon uterine contractions. To decide this question, it is first of all necessary to determine how the foetus lies if solely under the influence of gravity, for the fo'tus in the uterus is, as well as all other things, subjected to the laws of gravity. In very numerous experiments, made first by Duncan, and then by Veit (loc. cit., p. 256) and Honing (loc. cit., p. 93), in which a foetus recently dead was allowed to swim in a balloon filled with salt water of a specific gravity equal to that of the foetus, it was seen that the head lies lower than the breech, and that the right shoulder looks downwards. The foetus lies in the posi- tion (only the right shoulder somewhat lower down) as represented in Fig. 7 after M. Duncan, (Obstetric Res., p. 26). This position Fig. 7. LS doubtless due to the greater weight, of the head and the liver. Thal Kehre, («Beitrage,' c\.c, p. 109) did not find the centre of gravity <-f the foetus nearer to the upper half ^\' the body is no proof that the above explanation is wrong, and Duncan has shown r I >bst. b'es..' p. -J-J, Annotations) that the specific gravity of the head i> greater than that of the decapitated trunk, and Kehrer himself has observed (I.e.. j». 1L0) that the head has a greater tendency than the breech to assume the downward position. Poppel, however, has found the centre of gravity to he nearer to the cephalic end. However, the observations made by Wit on Heating foetuses have$