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Causes of Fluctuations in the Birth-rate. 



IT is not surprising, in view of the fundamental 

 importance of population, that the declining 

 birth-rate, which began in England in 1876 (in 

 France much earlier), and has now become 

 general in most civilised countries having accu- 

 rate records, has been the subject of numerous 

 studies. At first crude birth-rates stated per 1000 

 of the total population were regarded as sufficing 

 for these studies. They did so when all that was 

 desired was to show the effect of births on the 

 increase in population. These birth-rates, how- 

 ever, failed to indicate the true fertility of the popu- 

 lation. Child-bearing in women practically occurs 

 only between the ages fifteen and forty-five : it 

 varies greatly in married couples, according 

 to the proportion of married women living at 

 different ages within these thirty years of life, 

 and according to the duration of marriage. 

 The age of the father has been found, in actual 

 experience, to have an almost negligible influence. 



There have been two major studies in which the 

 subject has been investigated and correction made 

 for these arithmetical causes of variation, one by 

 Newsholme and Stevenson, which appeared in the 

 Journal of the Statistical Society in 1906, and 

 another by Mr. Udny Yule, published at the same 

 time in the same journal. The results of these 

 investigations are summarised in an interesting 

 paper now before us.^ 



The facts show that the decline in the birth- 



1 "The Fall of the Birth-rate.' A paper read before the Cambridge 

 University Eugenics Society. May 20, 1920, by G. Udny Yule. Pp.43. 

 Cambridge : At the University Press '920 ) 4^- net. 



NO. 2708, VOL. 108] 



rate is due chiefly to a fall in the productivity of 

 married couples, and that this fall has been pro- 

 ceeding at an accelerating rate. They show also 

 that there are great differences in the birth-rate 

 in various social strata, and it is likely that the 

 decline in fertility has been greatest in the pro- 

 fessional and upper classes. It has, however, 

 been great in many artisan circles, and especially 

 in the textile districts. 



What is the interpretation of these facts? Mr. 

 Yule disagrees with Dr. Stevenson, of the General 

 Register Office, in his view that the decline in fer- 

 tility of married women is *' due to the increasing 

 practice of contraceptive measures." That such 

 measures are largely practised, that they are 

 becoming increasingly practised, that they are 

 advocated by a large number of people who 

 believe over-population to be the chief cause of 

 poverty, that clinics for teaching married women 

 contraceptive measures have been formed, and 

 that a large mass of cheap literature on the sub- 

 ject is circulated, are all facts beyond dispute. 

 The facts that the decline in the birth-rate has 

 been greatest among the educated classes and least 

 among agriculturists and miners, who would be 

 less likely to be "made wise" on the subject, 

 and that the beginning of the fall in the birth- 

 rate corresponded in time with the Bradlaugh- 

 Besant prosecution for publishing " The Fruits 

 of Philosophy," undoubtedly support this view. 

 But in Mr. Yule's opinion it is too simple an 

 explanation ; and he justly urges that even if 

 these measures constitute the chief means for 

 reducing fertility, they do not explain the almost 

 universal desire for such reduction. 



Is there any evidence of variations in fertility 

 in circumstances in which contraceptive measures 

 may be assumed not to have been in use? In 

 some small group-inquiries this appears to have 

 occurred, though the evidence is not conclusive. 

 Mr. Yule's main point rests on the discovery of 

 instances in which an increased birth-rate has 

 occurred in circumstances in which the artificial 

 prevention of conception in the period of lower 

 birth-rate can be excluded. He produces a soli- 

 tary instance, that of Connaught, the true fer- 

 tility in which was 35 to 39 per cent, greater, in 

 191 1 than in 1881, and 6 per cent, greater 

 in 1871 than in 1881. This being an almost 

 purely Roman Catholic area, the use of contra- 

 ceptives may probably be excluded. One mav, 

 however, doubt the accuracy of the birth 

 statistics of this area. As pointed out in another 

 part of Mr. Yule's paper, compulsory registra- 



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