According to the latest doctrine of sterility, only in quite exceptional instances is the woman regarded as responsible for the occurrence of sterility; contrariwise, the male genital organs are commonly blamed for the affection, which is in the overwhelming majority of cases supposed to be due to azoospermia, usually dependent upon gonorrhœal infection; compare with this, affections of the female reproductive organs are said to play a quite subordinate role in the etiology of sterility. But for my part, though I recognize the important share that gonorrhœa in the male plays in the causation of sterility, I am of opinion that the extreme view just mentioned is by no means justified by the facts.
Sterility, a functional disturbance of an extremely complicated nature, can, in my opinion, be most usefully elucidated from the etiological standpoint by starting with the assumption that three conditions are absolutely essential to procreation:
1. that ovulation proceeds in a perfectly normal manner, the maturation of the discharged ova being complete;
2. that normal spermatozoa have access to these normal ova (conjugation of male and female pronuclei);
3. that the uterus is properly adapted for the gestation of the fertilized ovum.
My classification of the varieties of sterility corresponds to these conditions of procreation:
1. sterility due to incapacity for ovulation;
2. sterility due to some hindrance to the conjugation of ovum and spermatozoon (under this head come also those cases in which the male is at fault—azoospermia, and the like);
3. sterility due to incapacity for gestation.
It must also be admitted that there are additional causes of sterility, causes which lie beyond our control. Moreover, as I have already mentioned, in most cases of sterility, we have to do, not with a single cause, but with the resultant of two or more cooperating causes.