540 THE PHYSIOLOGY OF REPRODUCTION 



O'OOo to 0'009 per cent., and Brocard 1 an upper limit of O'Ol per 

 cent. Zacharjewsky, 2 however, observed no increase in the reducing 

 power of the urine on an ordinary diet during the last weeks of 

 pregnancy. The first definite increase comes with the appearance 

 of lactose in the urine after birth, though it may also be excreted a 

 few days before birth. It is more evident when the milk is not 

 utilised and becomes re-absorbed, but it rarely exceeds 0'3 per cent. 3 

 Extirpation of the mammary glands immediately stops the lactosuria, 4 

 and, if carried out in pregnancy, prevents it. 5 In 2200 consecutive 

 cases Cron found sixty-eight, or three per cent, of pregnant women 

 whose urine gave a test for the presence of some reducing sugar; 

 seventeen women gave a positive reaction during the puerperium. 

 Cron points out that the presence of a reducing sugar during 

 pregnancy or the puerperium is usually due to lactosuria or to 

 alimentary glycosuria, and this condition must be distinguished from 

 diabetes mellitus and other types of glycosuria. He estimates that 

 '50 '50 per cent, of pregnant women may at some time or another 

 present an alimentary glycosuria. 



Numerous observations 7 on the blood sugar during normal 

 pregnancy fail to show any deviation from the normal in women. 

 In rabbits Schirokauer 8 believes to have noted an increase ; in two 

 bitches Oppler and Rona 9 failed to find any difference before and 

 after they had littered. During labour the blood sugar rises and 

 falls again in the puerperium. Very high values were found in 

 eclampsia if the blood was taken immediately after a convulsion. 

 This suggests that the hyperglycremia of labour is related to the 

 increased activity of the muscles. 



The glycosuria of pregnancy has been ascribed to a diminished 



1 Brocard, " La Glycosurie de la Grossesse," These de Pan's, 1898. 



2 Zacharjewsky, loc. cit., Zeitsch. f. Biol., vol. xxx., 1894. 



3 The inability of the organism to oxidise lactose was demonstrated by Voit 

 (" Verhalten der Zuckerarten im menschlichen Organismus," Deut. Arch. f. klin. 

 Med., vol. Iviii., 1897). 



4 Sin6ty, "Urine of Guinea-Pigs in Puerperium," Ctnnpt. Rend, >Soc. Biot., 

 vol. 1. 



5 V. Noorden, loc. cit., vol. i. (see also pp. 602-605). 



6 Cron, "Glycosuria during Pregnancy," Amer. Jour. Obst. and Gyncec., 

 vol. i., 1920. 



7 Benthin, "Der Blutzuckergehalt in der Schwangerschaft, in der Geburt, 

 im Wochenbett und bei Eklampsie," Zeitsch. f. Geburtsh. v. Gyndk., vol. Ixix., 

 1911. Neubauer and Novack, "Zur Frage der Adrenal inaemie und des 

 Blutzuckers in der Schwangerschaft," Deutsche med. Witch., 1911. Bergsma, 

 " Der Zuckerstotfwechsel in der Schwaugerschaft," Zeitsch. f. Geburtsh. n. Gyniik., 

 vol. lxxii.,'1912. Ryser, "Blutzucker wahrend der Schwangerschaft," Deutsch. 

 Arch.f. klin. Med., 1916. 



8 Schirokauer, "Zum Zuckerstoffwechsel in der Schwangerschaft," Berl. kiln. 

 Woc.h., 1912. 



9 Oppler and Rona, " Untersuchungen tiber den Blutzucker," Biochem. Zeitsch., 

 vol. xiii., 1908. 



