444 REPRODUCTION AND DEVELOPMENT 



intestinal movement. The former cause results in nausea ("morning- 

 sickness") lasting sometimes almost from conception onward even for 

 four months or more. Sometimes it brings about a curious craving for 

 all sorts of unusual articles of diet, as well as for the chalk, earth, lime, etc., 

 often craved by young children. 



The blood and its circulation undergo changes of much less practical 

 importance. The changes which occur are less than was formerly 

 supposed; for example, Ehrlich denies that the number of the blood- 

 corpuscles is changed in any recognizable degree. Measurements of the 

 erythrocytes of twenty-two pregnant women (Rosthorn) showed no 

 change in their size, although there were many of a diameter greater than 

 normal. No nucleated red corpuscles could be found, yet the indica- 

 tions were that regeneration of the corpuscles was unusually lively. The 

 percentage of hemoglobin increases slightly and considerably (15 per 

 cent.) postpartuA. There is a very moderate leukocytosis. The blood's 

 alkalinity is slightly lessened; its specific gravity is unchanged from the 

 usual figure (1055). 



It is likely that a certain amount of what one might call functional 

 hypertrophy of the heart at least obtains as in all muscles when used 

 more actively than before, but its degree is slight; no increase in blood- 

 pressure for example, is discoverable. The heart's apex is displaced 

 upward by the abdominal pressure, and it was this which formerly gave 

 the impression of enlargement. The right heart seems to be under 

 more extra strain than does the left heart. It is not at all likely (von 

 Rosthorn) that any pulse exists characteristic of- pregnancy. 



Respiration is rendered difficult to a degree dependent on the increase 

 in size of the abdomen. Despite the additional demand for more oxida- 

 tion made by the fetus, the hypertrophied uterus, etc., the inspiratory 

 movements are more or less impeded by the presence of the enlarged 

 uterus in the belly. This gives rise to a degree of dyspnea that is usually 

 however, of small annoyance. 



The nervous system during pregnancy becomes both more sensitive 

 and more irritable. The former change shows itself in the additional 

 acuteness which the senses exhibit. The increase in irritability is mani- 

 fest in numerous ways, especially in "nervous" primiparse, for conditions 

 which before did not trouble or worry them now become occasions of 

 irritation. 



Changes in the urine are many, but it is not certain that they may all 

 be said to be normal. In general the amount is increased, with a corre- 

 sponding decrease in density. In about 5 per cent, of pregnancies (some 

 observers say many more) some degree or other of albuminuria is to be 

 found. Glycosuria too is to be found in a variable percentage of preg- 

 nancies. Acetonuria is to be found in all cases of pregnancy, but in 

 only 28 per cent. (Stolz) does its degree overstep the normal figure. The 

 sulphates of the urine and especially its phosphates are lessened in amount, 

 being used perhaps in forming the fetus. The ammonia of the urine 

 increases during pregnancy. 



