Most science curricula teach children and young people, at some point, how an egg is fertilised at conception and an embryo goes on to implant in the uterus, grow and develop over nine months before birth - indeed I teach my class of ten year olds about this. Whilst many are familiar with which features are visible at various stages of gestation, most of us don’t really study the very early development in detail – the development before visible systems emerge. It’s quite a beautiful process really, so here I’ll try to explain some of the points of note and explore their relevance to pro-life thinking.
Occasionally, the original cell replicates to two individuals, creating identical twins. Some might argue that this negates my previous point, but I don't accept that. This is the very first thing that happens, the very first cell division. It occurs through a process called mitosis, where the cell is replicated and two exact copies are created, so no individual has been destroyed.
What follows is an exponential increase in cell numbers; 2, 4, 8, 16 etc., all identical 'stem cells' with potential to develop into any cell (hence the desire of some to destroy the early embryo for research into using these cells for undoubted medical benefits - that's one for another blog). It is only then that the embryo implants into the wall of the mother's uterus and the really interesting stuff starts to happen!
Sometimes, however, conception occurs but the embryo fails to implant. This is called a 'spontaneous abortion'. It is sometimes due to bad luck; it doesn't come into contact with the uteral wall. This is not uncommon and some would argue that this is another reason to debate the legitimacy of the embryo as a human life. However, if you believe in life from conception to natural death, it is just as tragic as a cot death, even though we don't know about it.
However, many of these spontaneous abortions are caused by contraception. One of the ways 'the pill' or 'the coil' work is by making the lining of the uterus unreceptive to implantation. In that sense it is abortifacient. It is a deliberate act leading to destruction of an embryo. So, any sexually active pro life women reading, stick to barrier contraception!
This raises questions as to when consciousness begins. We clearly have a living organism with a CNS. John Harris at the University of Manchester, where I studied, claimed that we can only define consciousness as when there is awareness of oneself - ie. I am separate from you, and this was the basis of his argument that abortion is ethical – babies in the womb know nothing else. However, infants don't start using personal pronouns - words that distinguish individuals - until long after birth and only 10% of 13 month olds will even recognise themselves in a mirror! Therefore, by Harris’ reasoning, a child has no consciousness for the first few years of its life. What a nonsensical argument! The CNS controls consciousness, and develops early on!
The body’s systems then develop and the embryo physically forms into a full term baby, ready to survive by itself. Many parents say that their pregnancy only became 'real' when they heard the heartbeat for the first time, but the baby had a brain (of sorts) long before.
In conclusion, the distinct individual is formed immediately at conception. The CNS develops very early on. These two facts clearly support the idea that life begins at conception. Simple.