First usage of the word "baby" to mean fetus or any synonym of fetus

Does anyone know of a source that would indicate the first (give or take) usage of the word "baby" to mean fetus or any synonym of fetus? Every reference I've found thus far points to the usual meanings, but none indicate this particular usage. Even so, "fetus" is listed as an alternate definition in the few dictionaries I've checked.

Thanks in advance for any feedback!

Solution 1:

Fetus was used to refer to a newborn child also in Latin:

• In Latin, fetus sometimes was transferred figuratively to the newborn creature itself, or used in a sense of "offspring, brood" (as in Horace's "Germania quos horrida parturit Fetus").

The Pregnancy Terms Glossary of Medical Terminology defines:

Fetus as:

• Medical term for the baby before it is born, ie when still in the uterus.

the AHD and the Collins Dictionary give one definition of baby as:

• An unborn child; a fetus.

Ngram show usage of the expression baby fetus from the 60's.

Solution 2:

No, I don't think this has ever been done. Fetus is an exact development stage. Baby is the generic catch all term. Thus you have the implication arrow pointing in the wrong direction. Fetus implies baby. But "baby" might mean a 5 year old boy or my fluffy eared Beagle.