Chorion Frondosum And Decidua Basalis

In the early weeks of development, villi cover the entire surface of the chorion (Fig. 6.7). As pregnancy advances, villi on the embryonic pole continue to grow and expand, giving rise to the chorion frondosum (bushy chorion). Villi on the abembryonic pole degenerate and by the third month this side of the chorion, now known as the chorion laeve, is smooth (Figs. 6.9 and 6.10A).

The difference between the embryonic and abembryonic poles of the chorion is also reflected in the structure of the decidua, the functional layer of the endometrium, which is shed during parturition. The decidua over the chorion frondosum, the decidua basalis, consists of a compact layer of large cells, decidual cells, with abundant amounts of lipids and glycogen. This layer, the decidual plate, is tightly connected to the chorion. The decidual layer over the abembryonic pole is the decidua capsularis (Fig. 6.10 A). With growth of the chorionic vesicle, this layer becomes stretched and degenerates. Subsequently, the chorion laeve comes into contact with the uterine wall (decidua parietalis)

Cytotrophoblast shell shell

Cytotrophoblast shell shell

Chorion Frondosum Photos

Syncytium Chorionic B



Spiral artery

Intervillous space

Blood vessel if | Cytotrophoblast

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Getting Back Into Shape After The Pregnancy

Getting Back Into Shape After The Pregnancy

Once your pregnancy is over and done with, your baby is happily in your arms, and youre headed back home from the hospital, youll begin to realize that things have only just begun. Over the next few days, weeks, and months, youre going to increasingly notice that your entire life has changed in more ways than you could ever imagine.

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