MENSTRUATION AND THE ENDOMETRIUM

SINCE HITSCHMANN AND ADLER (1) first described the cyclic changes in the endometrial glands and Schroeder (2) correlated these changes with corresponding rhythmic phenomena in the ovaries, many investigators have searched the eiv dometrium for an explanation of the mechanism of menstruation. The introduction of the suction biopsy (3) in 1932 has made it a simple matter to obtain human endometrium at frequent intervals. Despite this aid the exact mechanism of menstruation remains unknown. While the condition of the endometrium is a fairly reliable index of ovarian function, it does not indicate if or when menstruation will occur (4). The purpose of this paper is to report two unusual cases which we believe cast additional light on this problem. It is generally believed that menstruation occurs as a result of degenerative changes in the endometrium following regression of the corpus luteum (5). In the normal ovulatory cycle, the secretory endometrium as a rule is cast off more or less completely during the first or second days of the flow.