Reflections on the duration of preganancy : with remarks on the calculation of the date of confinement / by J. Matthews Duncan.

  • Duncan, J. Matthews (James Matthews), 1826-1890.
Date:
1854
Catalogue details

Licence: Public Domain Mark

Credit: Reflections on the duration of preganancy : with remarks on the calculation of the date of confinement / by J. Matthews Duncan. Source: Wellcome Collection.

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    nation and parturition by three days; and we may argue from this with some little probability, that conception takes place generally a few days after menstruation is finished—a view which is confirmed by numerous other physiological observations. THE PREDICTION OF THE DAY OF CONFINEMENT Is one of the functions ascribed to the accoucheur; and apart from the comfort and convenience to the mother attending the foreknow¬ ledge of it, she often makes its failure or success a test of the more subtle acquirements of the physician. The foregoing statistics, however, will always justify the latter in never giving a decided prognosis of the day of confinement; and if he have been guarded and careful, will afford him asylum, showing, as they do, that with certain knowledge of the termination of the last menstruation, or even of the date of a single coitus, no safe prediction can be made unless within limits so extended as to deprive it of much of its value. At the same time, there is no doubt it will always be a desideratum to know the most probable day of confinement—and this can generally be settled with some exactness. If the date of a single connection is ascertained, which is, of course, very rarely the case, then the process of deciding the pro¬ bable day of confinement simply consists in telling off 275 days (the average interval between insemination and parturition) from that date. Now, any nine consecutive calendar months include 275 days, if February is not in the number. If February is in the number, the nine calendar months include only 273 days, and the correction necessary is apparent. The whole process of calculation, then, consists in attaching the number of the day of connection to the name of the month, ninth succeeding, and adding two addi¬ tional days if February is included in the interval.1 In the vast majority of cases, the day of confinement is predicted from the date of the termination of the last menstrual period. In many cases, the calculation can be aided and corrected by compari¬ son with former pregnancies in the same female. But when this source of information is wanting, the nearest approach to truth will be made by adding to the day of the disappearance of the menses 278 days (the average interval between the end of menstruation and parturition). The prediction will, of course, prove erroneous in a great number, nay, in the majority of cases, but it forms the nearest approximation which the mother can obtain to guide her. If a woman, then, knows the last day of her last period, she has only to tell the same day for the ninth month following (most mothers do so on their fingers, which thus form an admirable periodoscope), and 1 Nine months do not always contain 275 or 273 days. Dating from De¬ cember and July, nine months contain 274 days, and from May 276. The statements in the text, although sufficiently correct for general use. require this correction to he exact.