how many days long is the secretory phase
6.1 Role and functional anatomy of the endometrium. 1  Introduction. 2  Functional anatomy of the endometrium. 3  Endometrial functions. 4  Cyclic hormonal alterations of the endometrium The menstruation phase. The follicular or proliferative phase. The luteinizing or secretory phase. During the secretory or luteinizing phase (14th to 28th day) the endometrium differentiates itself due to the influence of progesterone (from the corpus luteum) and attains its full maturity. The glands and arteries begin to entwine. The connective tissue stroma becomes the place of edematous changes. The time period of the maximal reception ability for the blastocyst lies between the 20th and the 23rd day. This phase of the endometrium lasts 4 days and is usually termed the  .