It is an abortion when a life is aborted—terminated, ended, ceased, stopped, is made dead.
A Homo sapiens is a human, and a human is a person.
To abort the life of a living being (all species) is to kill. To abort the life of a human being (Homo sapiens) intentionally is murder. Though, whether it is technically murder or not is based on, let’s say, how society is feeling: It is OK to kill and is therefore not murder and is therefore not punishable by law if the person is x, with x being, for example, “a non-person (female),” “disabled,” “a slave,” “violent,” “the enemy,” “a criminal,” “sick.” What is x to you? (To note, to discriminate a person based on age is ageism, and to discriminate a person based on ability is ableism.)
Humans reproduce via sex(ual reproduction)—as opposed to asexual reproduction. The egg and the sperm are living reproductive cells. Mitosis and meiosis only happen in living cells. A unique Homo sapiens is created at conception. A zygote, a fetus, a baby, a child, a preteen, a teen, a young adult, an adult, and a senior are different life stages, different stages of development, of a human: same person, different age.
Simply, to be pro-choice is to be OK with the killing of a person.
Why you want abortion as an option and why you think you, and not someone else, have the right to that choice are different matters.
But to want to justify abortion with biology indicates denial and a lack of education. Accept abortion for what it is.
>condoms break! Birth control fails! Accidents happen!
The biological and primary function of sex is to make babies. If you don't want babies, don't have sex. It's really not that hard. "Accidents happen" is not an excuse to kill children.