Scanning electron microscopy of the endometrium in functionally agonadal women receiving steroid replacement therapy with polysiloxane vaginal rings and cylinders.

We prepared a group of five agonadal women to receive donated embryos by delivering physiologic concentrations of 17 beta-estradiol (E2) and progesterone (P4) through a polysiloxane vaginal ring and cylinder delivery system. In order to detect endometrial surface ultrastructural asynchrony that might reduce prospects for successful embryo transfer, we performed scanning electron microscopy (SEM) on biopsies obtained from these five women and compared them against those from four normal, spontaneously ovulating controls. Light microscopy revealed all nine women to be in the late luteal phase (day 26 +/- 2) and with glandular-stromal synchrony. Further concordance was seen with SEM, with no discernible difference in the development of cilia, microcilia or apical secretory protrusions between the two groups. SEM, a technique that permits visual assessment of endometrial surface topography, demonstrated that this regimen of native E2 and P4 restored the surface ultrastructure of the prematurely menopausal human endometrium to correspond to that in the normal menstrual cycle.