SEX IN LIVING FORMS 



3. The place of imbedding must be ready, and pre- 

 pared to form the menstrual decidua. 



If these conditions are not present, the next men- 

 struation will be abnormal. To this category belongs 

 amenorrhea. 



1. No ripe ovule is developed, or it is of diminished 

 vitality, and consequently is not imbedded; or if im- 

 bedded, after a few hours or days it dies, and a real 

 menstrual decidua has not been developed; conse- 

 quently no hemorrhage takes place. If during the 

 short time the ovule is in the uterus, spermatozoa 

 should enter, pregnancy might take place, which ex- 

 plains those rare cases of pregnancy occurring during 

 amenorrhea. During lactation, the absence of or weak 

 ovules would explain the absence of menstruation, and 

 the occasional occurrence of pregnancy at this time. 



2. If during menstruation, from some cause no ripe 

 ovule is present, none can be imbedded, no menstrual 

 decidua is formed, and the next menstrual does not 

 appear. The menstrual congestion which aids the de- 

 velopment of the Graafian follicle and ripening of the 

 ovule being absent, the ovules are weak, do not become 

 imbedded, or if they do, die in a short time. The amen- 

 orrhea continues until a strong, healthy ovule is again 

 imbedded, and then dies, causing the menstruation. 

 This also explains why pregnancy can occur after long- 

 continued amenorrhea. 



Cases occur where two or more causes are present 

 to prevent imbedding of an ovule, and to cause amen- 

 orrhea. 



Anomalies of menstruation, such as profuse and 

 irregularly recurring hemorrhages, can be readily ex- 

 plained, as they have no connection with menstruation 

 at all, in fact, often occurring during amenorrhea, and 



