To be honest Smiffy, it’s the one pro-life argument I’ve ever actually encountered. Most people who are pro-life (not including the YD, Alive Iona Institute types) aren’t the kind of people who want to see contraceptives, divorce, gay marriage etc. legally prohibited. If the YD, Alive and Iona types were what was holding back abortion on demand, then it would be available in the same way that contraceptives and divorce are.
And to be fair to the Iona Institute types, even though their arguments tend to be derived from Catholic teachings, the relevant Catholic teaching in the case of abortion relates to the belief that once their is a human body, there is a human soul and the human being is a complete. In this sense, even that argument is a human rights argument.