PINOPODES AND ITS MORPHOLOGY – MARKER OF IMPLANTATION WINDOW Moscow Medical Academy IM Sechenov 2009 Prepared by 4 th year students, Ang Hui Min & Wong Wei Xiang Supervised by Prof E.A. Kogan

Successful Implantation = intrusive Blastocysts + receptive Endometrium he Implantation Window A brief period of time during menstrual cycle when human endometrium becomes receptive to implantation by the blastocyst T

The Implantation… The follicular or proliferative phase is separated by ovulation on day 14 from the luteal or secretory phase. Implantation possible – Luteal 20-22d (implantation window) ABCDABCD Menstruation Proliferation Secretion Implantation window

hat is in the endometrium? Among the ultrastructural hallmarks of secretory endometrial epithelial cells are giant mitochondria, subnuclear glycogen deposits, pinopodes and nucleolar channel systems (NCSs) W

Pinopodes Nuclear Channel System (NCSs) Early luteal Phase Potential markers of implantation window MenstruationSecretory/Proliferation giant mitochondria subnuclear glycogen deposits

The proposed scheme of implantation window

Pinopodes Nuclear Channel System (NCSs) Early luteal Phase Potential markers of implantation window MenstruationSecretory/Proliferation giant mitochondria subnuclear glycogen deposits

small elevations at the apical pole of the epithelial endometrium cells Pinopodes (Uterodomes) 1

Facts about pinopodes... Appear during implantation window period consume energy promoted by Increase serum progesterone Decrease glandular progesterone receptor B expression inhibited by estrogen.

High level of Progesterone Not-so-high level of estrogen **Hence pinopodes is possible to appear in any period of the secretory phase!

Morphology development of Pinopodes in 2 nd half of menstrual cycle Pre-implantation period Implantation window Post-implantation

Preimplantation period Day 14 P+2 LH+1 Day P+3,4 LH+2,3 Day 17 P+5 LH+4 Day 18 P+6 LH+5 LH producesCell begins to swell, especially center of cell. Full swelling of cell that involved cell apex. Microvilli reaches their maximum development Microvilli decreases in size, their tip appears to be swollen

SEM on DAY-18… Moss or uterus ??

Implantation window Day 19 P+7 LH+6 Day 20 P+8 LH+7 Day 21 P+9 LH+8 Day 22 P+10 LH+9 Marked cells swelling Microvilli start to degenerate in size and in number Some appeared to fuse together or disappear all together. Slender and smooth membrane projection of entire cell apex Microvilli is totally absent. Membrane protrusion protruded and folded maximum Membrane swelling start to regress Appearance of microvilli again Cell increased in size Pinopodes disappear Numerous microvilli

Postimplantation period Day 23 P+11 LH+10 Day 24 P+12 LH+11 Full size of cellCell retained its dome shaped and covered with short stubby microvilli

Lateral plasma membrane changes during implantation window Mv -microvilli Tj-tight junction Tw-terminal web D-dermosomes Bl-basal lamina

Conclusion Pinopodes appear only during the implantation window period hence its known as the marker of implantation window. The microvilli on the epithelium disappeared during the formation of pinopode. Formation of pinopodes is followed by the increased number of tight junctions with the thickening of basal lamina of the endometrium epithelia. Number of pinopodes in endometrium is closely associated with the occurrence of pregnancy.

% of pinopodes on endometrium Type% of pinopodes on endometrium No of patientPregnancy% of successful pregnanacy Abundant> Moderate few<20500

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