The results of the investigation may be thus summarized:I. Concerning immediate data we find that among the 60 cases there were 33 primaparaS and 27 multiparas. There were eight cases associated with pregnancy and in 52 psychoses followed childbirth. The onset of psychosis during pregnancy was found to be gradual, characterized by instability, unrest, mild anxiety, depressive mood with swing to elation, usually accompanied by insomnia and sometimes by headaches. In the post-partum psychoses the onset was rather sudden. In the majority of cases it would begin with excitement, in others with depression. The usual onset was between the first and fourteenth day. It was quite characteristic that the onset was related to the time of the patient's return home from the hospital, which was usually the tenth or twelfth day post-partum. At any rate the psychosis manifested itself during sub-involution, a point which, as will be seen later, is of importance. In case the onset was later there were prodormal signs during sub-involution. In the beginning there was very often a somatic element present, the more pronounced the closer the onset was to delivery.II. Personality data can be tabulated as follows:See table in the PDF fileIn the manic-depressive group there is often a history of a previous attack and there are cases which show a manic state of affairs during each pregnancy or after each childbirth. In the majority of cases the total affectivity and impulse-life are harmoniously integrated. Manifested affect whether elation or irritability is evenly distributed, everything pleases or irritates the patient, there is no exclusive investment of affect, but rather pathological accentuation.In schizophrenia the situation is quite different. There is obvious discord in integration of affectivity and impulse. We often meet, for instance, an insecure impulse and differentiated affectivity which may result in deceptive outward manifestations; for example, shyness and seclusiveness often harbors a rather strongly differentiated impulse. Moreover affectivity is not flexible, often exclusively and unmovably invested, and dissociation is present.Our findings concerning pre-psychotic sexual life such as frigidity are confirmatory to the findings of Anderson. While frigidity may be present, it is not particularly prominent. The age of marriage of our patients was between the ages of 16-28.Intersexual conditions were present in both groups. Again it is differently expressed in the two groups. If we consider the sexual impulse as a certain form of energy originally released by a biochemical, hormonal principle and evoluting into a force of infinite organic and psychological complexity, we find that the psychological component plays a greater rôle in the manic-depressive cases than in schizophrenia. On the other hand, impulse is of greater significance in the schizophrenic. Male distribution of bodily hair which is associated often with genital hypoplasia and dysplasia are more conspicuous in schizophrenia. In the manic case a very interesting feature is the outline of hair of the fronto-parietal region which has the masculine convex form, and which is quite pronounced. Activity is often of masculine order, the voice may also have a male character in the manic.III. Mental content. The ideation in the manic state is the usual one. The patient usually betrays her aspirations and solves them in a grandiose manner, for instance, a patient who is very fond of children expresed the idea that she is going to have more children and immediately. In case of rejection of the husband the cause is very easy to trace and is referrable to social or biological inferiority of the husband; for example, a patient who had superior cravings and whose husband was inferior to her in both aspects, spoke in her psychosis of marrying the Prince of Wales. They may sometimes deny marriage, but there is no such absurd compensation as in the schizophrenic. No infanticide ideas were met in the manic state but such ideas are not infrequent in depression. We shall discuss this point presently; the depressive phase offers otherwise the usual syndrome.The ideation of the schizophrenic is differently expressed. We are interested for the present in the question of rejection of the marital situation. The denial of the latter may assume a bizarre form, and its expression is a matter of degree. From simple hostility it may progress to ideas of virginity and further to identification with the Holy Virgin. Ideas of infanticide are common. Here we can trace at least two ways of their construction. In certain schizophrenics and in the depressed phase our findings are confirmatory to those of Hopwood. We find the primary idea to be suicide, which overflows and may enclose husband and child. (We have discussed the possible mechanism of suicide in another study.) In cases of this type infanticide seems to be prompted by the affect of sorrow for the fate of the family. It is of interest that in the pre-psychotic personality of such patients we find sentimentality to be an outstanding trait. In other cases infanticide must be regarded as a projective expression, and belongs primarily to the domain of impulse. The projection is also a matter of degree. It may involve child, husband and may progress to ideas of world destruction. In certain cases of catatonia when the extreme excitement or stupor subsides the patient may have no recollection of her previous ideation (such amnesia being often unjustifiably doubted). This seems to go with White's interpretation of catatonia on psychological lines when he states that the catatonic endeavors to shut out from consciousness his conflict by a supreme effort of repression. Biologically we like to interpret this as a vigorous effort on the part of the auto-regulation of functions ("biological conscience," von Monakov) to restore balance.IV. Pathological data. In conjunction with our other work we have reason to believe that certain autopsy findings are of considerable importance for our problem. We wish to call attention to the damage to the reticulo-endothel which is quite pronounced and to ovarian changes. The latter have shown considerable damage. The changes suggested circulatory disturbance which obviously must impair nutrition and consequently secretion, with luteinization and conspicuous reduction of graafian follicules. We shall discuss these findings in conjunction with otherwise well established physiological changes which occur during pregnancy.