OVARIAN PREGNANCY. 255 



and a normal corpus luteum, and the presence of a blood-clot within the ovary, 

 there would seem to be little reason for doubting the authenticity of the ovarian 

 implantation, even in the absence of embryonic remnants. Since changes suggest- 

 ing decidual reaction in the ovary have been reported so seldom, it is doubtful 

 whether much emphasis can be laid on them. One seems justified in saying this in 

 spite of the fact that the presence of decidua in the ovary formed the only ana- 

 tomic evidence upon which Kantorowicz (1904) confidently classed his two rather 

 advanced cases of ectopic, among authentic ovarian pregnancies. Moreover, if it 

 be true, as stated by Webster (1904), that changes which can not be distinguished 

 from true decidual changes not infrequently occur in the ovary in connection 

 with normal uterine pregnancies, then the presence of islands of pseudo-decidual 

 cells in an ovary surely can not be regarded as indicative of ovarian pregnancy. 

 Perhaps, however, with modern histochemical methods, it would be possible 

 to distinguish genuine decidual cells. In making this observation, we are fully 

 aware that various criteria have been advanced from time to time by means of 

 which to judge ovarian pregnancies, and that many of these have met with objec- 

 tion and have hence been modified. Such modifications would seem to be inevi- 

 table as long as there is progress in the solution of an unsettled question. 



The absence of the fetus in many of the recorded cases in itself demonstrates 

 the entire inapplicability of the criterion added by Jacobson (1908). Moreover, 

 the histologic appearance of the ovarian tissue around certain portions of the 

 blood-clot in the present, and also in some of the cases in the literature, would 

 seem to suggest that it may be very difficult to find remnants of ovarian tissue at 

 several points in a case of pregnancy which has advanced far. Hence this criterion 

 of Spiegelberg (1878) can not be regarded as necessarily crucial. Whenever the 

 implantation is developed at the outer instead of at the inner margin of a follicle, 

 as in the case of Banks (1912), early destruction, even if not early rupture, of the 

 overlying ovarian stroma and capsule would seem to be inevitable. Indeed, 

 whenever the layer of ovarian stroma overlying the placenta is thin, very early 

 death of the fetus would seem to be inevitable from defective nutrition alone. 

 On the other hand, when placental development occurs in the region of the follicle 

 directed toward the body of the ovary, great destruction of the ovarian stroma 

 would seem to be unavoidable, even if something akin to normal decidual forma- 

 tion actually took place. In the case of Engelking (1913), for example, not a trace 

 of an ovary was found in an ovarian pregnancy which had become interstitial. 

 Even without assuming the complete authenticity of this rather equivocal case, 

 it would seem highly probable that the presence of ovarian tissue later in the preg- 

 nancy probably is determined very largely by the location of the fertilized follicle 

 within or by the exact location of the implantation upon the ovary. 



From evidence contained in the literature, it is clear that further reports of 

 single cases are not needed for the purpose of emphasizing the occurrence of ovarian 

 pregnancy, yet such reports nevertheless may help in the determination of the 

 relative frequency of this novel and sinister condition, and also throw further 

 light upon its genesis and the finer relations of the implantations, as well as upon 



