I. DEFECTS AND DISEASES OF THE OVARIES 

 I ■ Congenital Defects of the Ovaries. 



The fundamental basis of fertility in the female is the living, 

 fertilizable ovum, which must be elaborated by the ovary, dis- 

 charged therefrom, canght up by the pavillion of the oviduct, 

 met and fertilized by the spermatozoa of the male and, migrating 

 along the oviduct, reach the uterine cavity and establish intimate 

 relations with the uterine walls, by which it may secure nourish- 

 ment. 



The function of the ovary is fundamental in character, elabo- 

 rating the ovum and discharging it when the ovisac ruptures. 

 This completed, the direct function of the ovary ceases and its 

 relation to fertilization and the maturation of the fetus is chiefly 

 at an end. Still, it exerts an influence. If the ovaries of a 

 pregnant animal are removed, there is a definite tendency toward 

 abortion and it seems that it is not the ovaries as a whole which 

 exert this influence upon the fetus, but the corpus luteum, which 

 remains at the seat of the ruptured ovisac, from which the im- 

 pregnation has resulted. According to Hess, if the corpus 

 luteum is forced from the ovary of a pregnant cow, she will 

 abort. Very rarely also the fertilization of the ovum occurs 

 while it is yet in the ovisac, but presumably only after its rup- 

 ture, while the egg remains adherent to the walls. Eventually 

 -this causes the exceedingly rare phenomenon of ovarian preg- 

 nancy. The completed function, therefore, of the ovary includes 

 ovulation, since it is immaterial how many ova the gland con- 

 tains until, by discharge, they become available for fertilization. 



The causes of non-ovulation are numerous and may consist 

 either in the failure of the ovaries to produce mature ova or of 

 the intervention of some obstacle to the rupture of the ovisac and 

 escape of the egg. 



Arrest in development or absence of the ovaries occurs with 

 approximately the same frequency as the analogous condition of 

 the testicles, with the exception that the female gland does not 

 fail to attain functional maturity because of defective location, 

 its normal adult position being within the abdomen, not widely 

 separated from the point of embryonic origin. 

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