CHANGES IN THE MATERNAL ORGANISM 497 



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 ^). 



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^ 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 0-125 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 fre- 

 quency with which the tissue fluids, e.g. in the lower extremities, 

 are increased." Baumm ^ 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 amounting 

 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 * 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 multiparae, 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, hmitations to the estimation of the 



^ See Y. Noorden, Metabolism and Practical Medicine, vol. i., section on 

 " Metabolism of Pregnancy." 



' Gassner," UeberdieVeranderuugdes Korpergewichtes bei Sohwangeren," 

 &o., Monatsschr. f. Geburtsh. u. Frauenkrankh., vol. xix. , 1862. 



' Baumm, " Gewichtsveranderangen der Sohwangeren," &c., Inaug.- 

 Disaert., Miinchen, 1887. 



* Zacharjewsky, " Ueber den StickstofEwechsel wahrend der letzten Tage 

 der Schwangerschaft," &c., Zeitschr.f. Biol., vol. xxx., 1894. 



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