chorionväggen

The chorionväggen, often translated as chorionic wall or chorionic membrane, refers to the outermost fetal membrane in mammalian reproduction. It develops from the trophoblast, the outer layer of the blastocyst, and plays a crucial role in the establishment and maintenance of pregnancy. Initially, the chorionväggen is a thin layer that surrounds the entire embryo. As pregnancy progresses, it undergoes significant differentiation and contributes to the formation of the placenta.

In humans and other placental mammals, the chorionväggen participates in the formation of the villi, which are finger-like projections that embed into the uterine wall. These villi increase the surface area for nutrient and gas exchange between the mother and the developing fetus. The chorionväggen also produces hormones essential for maintaining pregnancy, such as human chorionic gonadotropin (hCG). This hormone signals the corpus luteum to continue producing progesterone, which is vital for preventing uterine contractions and supporting the uterine lining. The chorionväggen, along with the amnion, forms the amniotic sac which encloses the fetus and amniotic fluid, providing protection and facilitating fetal movement. The integrity of the chorionväggen is therefore critical for a healthy pregnancy.