cytotrophoblast

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Last updated

June 25, 2026

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The cytotrophoblast is an inner layer of the trophoblast, which is the outer layer of cells that forms the placenta during pregnancy. The trophoblast has the unique ability to invade and attach to the uterine wall, playing a crucial role in the development of the placenta.1

The cytotrophoblast specifically lines the cavity within the trophoblast and forms finger-like projections that extend into the syncytiotrophoblast, the outermost layer of the trophoblast. These projections will eventually become the core of the placental villi, which are responsible for absorbing nutrients and oxygen from the mother's blood. The cytotrophoblast is a key component in establishing the uteroplacental circulation, which sustains the fetus.1

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pregnancy
The uterus and the development of the placenta
The cytotrophoblast, which lines the cavity, forms fingers of proliferating cells extending into the syncytiotrophoblast. After the placenta is developed, these fingers will be the cores of the rootlike placental villi, structures that will draw nutrients and oxygen from the maternal blood that bathes them. This…
Read More
The cytotrophoblast, which lines the cavity, forms fingers of proliferating cells extending into the syncytiotrophoblast. After the placenta is developed, these fingers will be the cores of the rootlike placental villi, structures that will draw nutrients and oxygen from the maternal blood that bathes them. This…
Read More