258 PHYSIOLOGY CHAP. 



of them showing on their surface the residue of the epithelial 

 protoplasm from which they originate (Fig. 113). In the chapter 

 already mentioned we have dealt at sufficient length with the 

 histological and chemical processes by which the milk is formed, 

 and with the influence of the nervous system on the secretion. 

 The general health of the mother suffers very little from the 

 profound changes which have taken place in the genital apparatus. 

 The feeling of tiredness, a natural consequence of the labour of 

 child-birth, disappears during the first few days, if the process 

 of involution of the uterus progresses physiologically. In about 

 a third of the cases of lying-in women, the puerperium is ushered 

 in by a shivering fit which follows the after-pains and lasts from 

 five to, ten minutes. This shivering is of no morbid importance ; 

 it is due partly to the cooling of the woman during the confine- 

 ment, partly to the withdrawal of the source of heat represented 

 by the foetus and its adjuncts, partly to the muscular fatigue 

 undergone during parturition and to the re-absorption into the 

 circulation of the catabolic products of the metabolism in the 

 muscles. During the first twelve hours after parturition there 

 is a slight rise of temperature (37-8-37-9), but the temperature 

 becomes normal again on the second day (36-5 in the morning, 

 and 37-5 in the evening). The pulse of the normal woman during 

 the puerperium is remarkable for its slowness (60-50-40 beats a 

 minute). This phenomenon (which is termed puerperal bradi- 

 cardia) is a very favourable prognostic sign, and usually disappears 

 after the first week. The frequency of the respiratory movements 

 is also diminished during this period. During the first week after 

 child-birth the quantity of urine increases ; it sometimes contains 

 lactose and traces of peptone. The secretion of sweat also increases, 

 causing a sensation of' thirst. Owing to the relaxation of the 

 abdominal walls and the effect of bland food, the expulsive activity 

 of the intestines is sluggish. After the first week the weight 

 of the body shows a falling-off, about 3-4 kgs., which is naturally 

 accounted for by the increased discharge of urine, sweat, lochia 

 and milk. This loss of weight is soon made up; indeed during 

 lactation the desire for food and the digestive capacity increase 

 and a tendency to put on fat is usually noticed. 



BIBLIOGRAPHY 



On pregnancy and the formation of the placenta the following works should 

 be consulted : 



ERCOLANI, G. B. Sull' unita del tipo anatomico della placenta nei manmiiferi e 

 nell' umana spece e sull' unita fisiologica della nutrizione dei feti in tutti i verte- 

 brati. Bologna, 1877. 



BAYER. Freund's gynakol. Klin., 1885. 



VON SPEE. Zeitschr. f. Morph. iii., 1896. 



LEOPOLD, G. Uterus und Kind. Leipzig, S. Hirzel, 1898. 



