when does the uterine lining become more vascular
Endometrium The endometrium is the inner epithelial layer, along with its mucous membrane, of the mammalian uterus. It has a basal layer and a functional layer; the functional layer thickens and then is shed during menstruation in humans. Some other mammals including apes, Old World monkeys, some species of bat , and the elephant shrew menstruate.[1] In most other mammals the endometrium is reabsorbed in the estrous cycle. During pregnancy, the glands and blood vessels in the endometrium further increase in size and number. Vascular spaces fuse and become interconnected, forming the placenta, which supplies oxygen and nutrition to the embryo and fetus.[2][3] The speculated presence of an endometrial microbiota[4] has been argued against.[5][6]
Fallopian tube The Fallopian tubes, also known as uterine tubes or salpinges (singular salpinx), are two very fine tubes lined with ciliated epithelia, leading from the ovaries of female mammals into the uterus, via the uterotubal junction. They enable the passage of egg cells from the ovaries to the uterus. In non-mammalian vertebrates, the equivalent structures are called oviducts.