CHANGES DURING PREGNANCY 523 



importance if she can cover this loss from her food. The setting of 

 the question runs thus: Is the maternal body deprived of protein, 

 fat, and other substances during and in consequence of the formation 

 of a new being, and is its store of these materials, after the resulting 

 birth, or at the close of the puerperium, less than before the advent 

 of pregnancy, or is this not the case ? An unprejudiced clinical proof 

 from human subjects points to the possible occurrence of both 

 conditions. Man}' mothers during pregnancy increase so slightly in 

 weight that their own tissues must have suffered loss during this 

 time, others become heavier to the extent of ten kilograms or more. 

 The investigation has not to determine whether the maternal organism 

 suffers loss or experiences gain, but to demonstrate under which 

 conditions of nourishment the one or the other appears. It has to 

 investigate whether and in what amount the needs of the mother are 

 increased, if her original condition is to remain unaltered while new 

 tissues are being formed " (Magnus-Levy 1 ). 



B. The Body-weight during Pregnancy 



Systematic determinations of the body-weight give some idea 

 of the effect of pregnancy on the. maternal organism as a whole. 

 Gassner 2 observed a progressive increase in weight, greater than 

 the increase in the weight of the foetus (about 1 kilo per month) 

 and the generative organs (about 01 25 kilo per month) together. 

 This is due to the increase in the other parts of the maternal 

 organism as a " result of the inactivity and good dietetic conditions 

 during pregnancy, and the frequency with which the tissue fluids, e.g. 

 in the lower extremities, are increased." Baumm 3 confirmed these 

 results. A diet necessary to maintain the body-weight in a woman of 

 the same size gave an increase in weight of a pregnant woman amount- 

 ing to an average of 1'777 kilo in the last month, of which 0'650 

 kilo represented increase outside the foetus and generative organs. 



Zacharjewsky 4 observed an increase in weight running parallel 

 to the increased weight of the foetus and uterus. Some days before 

 birth he found a decrease in primiparse and a balance in multipart, 

 which he referred to Ahlfeld's observations that the foetus increases 

 only up to the thirty-ninth week, and in the last week decreases. 



There are, however, limitations to the estimation of the total 



1 See v. Noorden, Metabolism and Practical Medicine, vol. i., section on 

 " Metabolism of Pregnancy." 



2 Gassner, " Ueber die Veranderung des Kb'rpergewichtes bei Schwangeren, 

 etc.," Monatsschr. f. (jfeburtsk. u. Frauenkrankh., vol. xix., 1862. 



3 Baumtu, " Gewichtsveranderungen der Schwangeren, etc.," I iiaug.- Dissert., 

 [iinchen, 1887. 



4 Zacharjewsky, " Ueber den Stickstoffwechsel wahrend der letzten Tage 

 ler Schwangerschaft, etc.," Zeitsch. f. Biol. t vol. xxx., 1894. 



