Once an egg is fertilized, where is it implanted?

The implantation of a fertilized egg, also known as a zygote, occurs in the uterus. After fertilization in the fallopian tube, the zygote travels down to the uterus, where it becomes a blastocyst and embeds itself into the uterine lining. This is a crucial step in the early stages of pregnancy, as successful implantation allows for the development of the embryo and eventually a fetus.

The uterus provides the necessary environment for the developing embryo, including a rich supply of blood and nutrients, and offers protection as the pregnancy progresses. The other locations mentioned, like the ovary or cervix, do not support this critical stage of development. In the fallopian tube, while fertilization occurs, it is not the site for implantation. If implantation occurs outside the uterus, such as in the fallopian tube, it can lead to an ectopic pregnancy, a condition that poses significant health risks.