Conceptus

Conceptus is a term used in embryology to refer to the product of conception at any point between fertilization and birth. This includes the embryo in early stages of development, and later the fetus. The conceptus also includes associated structures like the placenta and the umbilical cord.

Development of the Conceptus

The development of the conceptus begins with fertilization, when a sperm cell from the male unites with an egg cell from the female to form a single cell called a zygote. The zygote then begins to divide and grow into a cluster of cells.

By the end of the first week, the cluster of cells has formed a structure called a blastocyst, which implants itself into the wall of the woman's uterus. The blastocyst continues to grow and develop, eventually forming an embryo.

The embryo is the stage of the conceptus from the second week of development until the end of the eighth week. During this time, all of the major organs and body systems begin to form.

From the ninth week of development until birth, the conceptus is referred to as a fetus. During this time, the organs and body systems continue to grow and develop, and the fetus begins to move and respond to stimuli.

Associated Structures

In addition to the embryo or fetus, the conceptus also includes structures that support the development and growth of the fetus. These include the placenta, which provides oxygen and nutrients to the fetus and removes waste products, and the umbilical cord, which connects the fetus to the placenta.

See Also

• Embryo
• Fetus
• Placenta
• Umbilical cord
• Zygote
• Blastocyst