“Fetus” refers to level of development

A couple of nights ago, I was having a conversation about abortion and my friend seemed confused over the meaning of the term “human fetus”.

I explained that “human” denotes that the creature is a member of our species and “fetus” indicates the level of development of the aforementioned human, much in the same way we use the words “infant”, “toddler”, “adolescent” and “adult”…

He seemed to really struggle with the idea that “elephant fetus” simply means an elephant at an early stage of development. So, with that in mind, have you ever wondered what an elephant fetus looks like as it’s growing to maturity?

Names for the unborn

Following on from yesterday’s post, recent discussions on Facebook have reminded me of how the abortion debate often turns around the question of language.

A few months ago I had posted an article about abortion and one of my friends wrote this response:

“You’re going to have a hard time convincing someone zygote development at 4 weeks is a fetus… When we talk in terms of a 6 week fetus it’s probably closer to bundles of cells than it is to a fetus…”

My friend’s response shows why it’s important to have a good grasp of biology when speaking about the unborn. What do we mean when we use words like “zygote”, “embryo” and “fetus”?

Development

“Zygote”, “embryo” and “fetus” are all simply labels which describe the developmental stage of the human child, much like “infant”, “toddler” or “teenager”. A zygote is a diploid cell which is the result of fertilization of an egg by a sperm. After about twenty-four hours, cell division begins and we move from the zygote phase of development to the embryonic. After eight weeks, we move from the embryonic to the fetal.

Hopefully it’s now clear as to why I’d never try to convince someone that “zygote development at 4 weeks is a fetus”…because it’s not! It would be as nonsensical as talking about an eight-year-old toddler or a twenty-year-old teenager.

Developmental Cheat Sheet

Zygote: Human development within the first 24 hours

Embryo: After 24 hours of life, when cell division has begun. It remains in this stage for the first eight weeks.

Fetus: A development stage following eight weeks of life up until birth.

Infant: Up to twelve months after birth

Toddler: 1-3 years after birth

Adolescent: The time after birth when conversation is exchanged for incoherent grunts and parents are treated as a cross between an ATM and a taxi service.

Regardless of the name we use to describe someone’s age, all humans deserve to be protected.