Fetus

A fetus or foetus (/ˈfiːtəs/; pl.: fetuses, feti, foetuses, or foeti) is the unborn offspring that develops from a mammal embryo.^[1] Following embryonic development, the fetal stage of development takes place. In human prenatal development, fetal development begins from the ninth week after fertilization (or eleventh week gestational age) and continues until the birth of a newborn. Prenatal development is a continuum, with no clear defining feature distinguishing an embryo from a fetus. However, a fetus is characterized by the presence of all the major body organs, though they will not yet be fully developed and functional and some not yet situated in their final anatomical location.

^ Ghosh, Shampa; Raghunath, Manchala; Sinha, Jitendra Kumar (2017), "Fetus", Encyclopedia of Animal Cognition and Behavior, Springer International Publishing, pp. 1–5, doi:10.1007/978-3-319-47829-6_62-1, ISBN 9783319478296

[:0-1] Ghosh, Shampa; Raghunath, Manchala; Sinha, Jitendra Kumar (2017), "Fetus", Encyclopedia of Animal Cognition and Behavior, Springer International Publishing, pp. 1–5, doi:10.1007/978-3-319-47829-6_62-1, ISBN 9783319478296

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