Pinopode

Pinopodes (also known as pinopods and uterodomes) are protrusions on the apical cellular membrane of uterine epithelial cells.

Pinopodes have a pinocytotic role (hence the name pinopode - Greek for "drinking foot"), as well as a secretory role. Their secretory vacuoles reach towards the lumen; The contents within the vesicle may provide necessary nutrients to the embryo. This feature also assists in its ability to attach to the uterine endometrium. With the development of pinipodes, there is a decrease in epithelial cell contact, which prompts blastocyst attachment and penetration.