SEX-INCIDENCE IN ABORTIONS. 



183 



sex nor age determination is any too reliable, and the ratios in the different 

 periods have therefore to be taken for what they are worth. Nichols's figures, 

 in abstracted form, are given in table J. His conclusion is that the "ratio of 

 male fetuses born dead is much the highest from the third to the fifth month; 

 much lower from the sixth to the eighth month; and at term the ratio again rises." 

 According to Carvallo (1912), the sex-ratio of abortions up to the fourth month 

 is 250; this figure he calculated from the statistics of Paris in 1908. Korosy (1898) 



TABLE I. Sex-ratio of abortions in different months. 

 (From Auerbach.) 



found the sex-ratio in 3,781 abortions to be 152.4 Pinard and Magnan (1913) 

 report on 1,229 abortions, the ages of which are not stated. This material showed a 

 sex-ratio of only 101.1. Rust (1902) also found the sex-ratio in 454 abortions 

 from the first six months to be very low, i. e., 101.8. It is apparent how greatly 

 these figures vary. A new contribution towards the knowledge of the sex-incidence 

 in abortions is therefore not valueless, especially as great care has been taken to 

 determine age and sex. 



TABLE J. Sex-ratio of abortions and still-births in differ- 

 ent months. (Adapted from Nichols.) 



TABLE K. Sex-ratio of 1,410 fetuses from different 

 months. 



The last paper of the writer on this subject (1918) was based upon a relatively 

 small amount of material; since then it has been more than doubled, increasing 

 correspondingly the dependability of the conclusions drawn from it. The material 

 in all consists of 1,410 fetuses, 1,249 of which are from the embryological collection 

 of the Carnegie Institution of Washington. For data on 32 fetuses, I am indebted 

 to Dr. Ingalls, and in addition I have made use of 57 fetuses published by Rauber 

 and of 72 Filipino fetuses tabulated by Ruth (1918). Of this material only a 

 small percentage is derived from induced abortions; the great majority were spon- 



