This is a very complex topic as it can involve a number of different scenarios where different laws, social and cultural factors are a big influence. For my argument I will presume that this is in a MEDC (more economically developed country).

A woman who gets pregnant because she has not used adequate protection (out of her own choice, not rape) should not be allowed to have an abortion. Is the cost of a human life because of a simple error, and because it is convenient, acceptable? take an analogy; recently in the news I'm sure you have seen the "baby P" scandal. The majority accept that the social services were negligent and that this caused a death which is, of course, wrong. Is that very dissimilar to a woman being negligent during sexual intercourse and then having an abortion? why should that be legal?

Now, I'm sure many people will say that there is no way to know if a woman has acted in such a way, to that I say simply the decision of abortion should lay entirely with a doctor to eliminate any possibility of this.

Other people say that a child which would otherwise of been aborted will be destined to a life in care. As awful as that may be, I can guarantee that almost all of those children when they reach an age of intellectual maturity will answer the question: would you rather of been dead and never have experienced life, EVEN if some parts were distressing etc.? with a no. They would quite simply rather be alive, a basic human instinct. Why should anyone decide whether a child can handle it's life or not.

I should also add that in a rape situation the same as above goes; whether the mother keeps a child conceived through rape or puts them into care, at the end of the day that child would rather be alive, modern therapy/psychology is at a very high standard so both the mother and child are not being left alone during this time. Rape is not something that should be used as an excuse for terminating a life. A child conceived through rape is has no reason to be worried about the social response, it doesn't make them less of a human, they still have the same number of chromosomes. Children have parents who are murderers, parents who have committed genocide, yet the children are still completely different, individual people who can still go on to be successful. you must weigh up both sides: yes the woman may be severely affected mentally but is this equal to a life? if there was risk of suicide then yes an abortion is an option but only qualified doctors should be able to make this choice.

In conclusion I would like to stress that this is only an argument for a MEDC with high quality health care etc.. in a LEDC/third world country I completely understand why some people would think differently. I believe that abortion should solely be a tool used by doctors in life threatening circumstances, normal people who are going through a distressing time are not able to weigh up the circumstances in a non-bias way. Surely only a life is equal to a life.