HYDATIFORM DEGENERATION IN TUBAL AND UTERINE PREGNANCY. 361 



From calculations based on data given by Lewis the average number of births 

 occurring after 40 years in Sweden, Norway, Denmark, Brunswick, Berlin, Buda 

 Pesth, France, and Scotland is 9.9 per cent. This agrees remarkably well with 

 Bloch's estimate of 10 per cent. But if 77.2 per cent of the cases of hydatiform 

 mole occur below 40, and 22.8 per cent after that year, then it is evident that 

 hydatiform mole nevertheless is relatively more common after than before 40 

 years, for approximately one-fourth of the cases of hydatiform degeneration would 

 be associated with one-tenth of the births. This would be an increased frequency 

 of 300 per cent above that before 40 years. A similar result would be obtained 

 by comparing Findley's or Williamson's series. Hence, hydatiform degeneration 

 though absolutely less is relatively more frequent in later life. This fact, however, 

 does not necessarily imply that age in itself is responsible for the increased incidence 

 after 40. A comparison of the incidences of hydatiform degeneration in young and 

 old primiparse, of good health, might elucidate this question. 



These statistics are not in agreement with the prevailing opinion that hydati- 

 form moles are more common in multipart than in primiparae. Indeed, as I under- 

 stand, they suggest rather that after the first conception, which was normal in a 

 large percentage of these young women, something happened which interfered with 

 the normal development of succeeding conceptions. That, it seems to me, is 

 extremely significant and very suggestive. Here is a group of relatively young 

 women, over 50 per cent of whom had borne but twice and some only once, and then 

 gave birth to a hydatiform mole. While I realize the necessity for circumspection, 

 especially in these matters, these facts seem to me to suggest that something hap- 

 pened to a normal endometrium. Other facts also point in the same direction. 



Even if it is not wholly correct, as Findley states, that more cases of hydatiform 

 mole were reported in the last decade than in the previous 14 centuries, it is not 

 unlikely that approximately as many specimens of this condition are contained in 

 the Mall Collection as have been reported heretofore. Moreover, upon the basis 

 of the present rate of accession, a large number of formerly unrecognized cases of 

 hydatiform moles both tubal and uterine are donated to this collection annually. 

 This fact, together with others to which attention has been called, ought to stimulate 

 our interest in this problem. 



