ChooChoo answered as follows :
I'm most grateful to him or her for this - the only information I've ever seen on the subject. If anyone's got any info on Britain I'd be interested.
I'd hesitate to say 'myth'. But there are problems with some figures and, of course, this is further problematised by the polemical contexts of inveterate debates. The US is interesting because abortion remains a livewire political debate: not just because of social dynamics, but also because of the legal context there. Unlike here, the (from one view) judicial fiat by which abortion was legalised in the states generates tensions beyond the usual ones in this debate.
In Planned Parenthood vs. Casey (Bob, a lifelong Democrat incidentally), the figure of 5,000-10,000 pre-legalisation deaths was mentioned. This figure, a common one in the US context, goes back to attempted extrapolations from studies from the 1930s, for instance, by one Frederick Taussig (published in '36). He used figures for the abortion rate (not the abortion mortality rate) from NY and Iowa birth control clinics, combined with his own estimates for the mortality rate to come up with the figures. (There were others which used similar techniques).
In reality, these figures are dubious and not least because of their use in polemical contexts. In 'Induced termination of pregnancy before and after Roe v. Wade', in the Journal of the American Medical Association, 208.22 (1992) pp.3231-3239, the authors use pre-legalisation figures for abortion mortality from National Center [sic] for Health Statistics:
1940 - c.1400
1945 - c.750
1950 - c.250
1955 - c.225
1960 - c.250
1970 - c.125
(The exact figure for pre-legalisation 1972 is 39. Abortion mortality figures still do exist post-legalisation, and the figure hovered around c.20 post-legalisation before dropping further in the 80s or 90s, I forget which).
These figures can hardly settle the question. First, they don't show how many total abortions there were. Second, they do not, in themselves, get into the difficulty of arriving at such figures. This difficulty, incidentally, is not just for finding reliable pre-legalisation figures, but also reliable post-legalisation figures. (Assigning abortion as cause of death is not as simple as it may sound). Third, these do not get into all sorts of social factors (was there a change in the public acceptability of treating women who had had abortions?). (These figures, per se, are far more reliable than, say, Taussig's).
Fundamentally, however, and this occurs in other contexts too, the large reduction in abortion mortality correlates to (and is no doubt caused by) medical provisions: most importantly, the diffusion of antibiotics. Medical provisions are more important in bringing down abortion mortality than legality. (This is not to deny that legality cannot or does not have an effect of safety: it does, but this relation is heightened where the safety, even where legal, would not be so good. Conversely, where medical provisions are good - not just supplies, but access - legality cannot have a strong effect on abortion mortality). In a first-world context, the notion that illegality will result in the death of scores of women is not tenable. (Another important aspect to this is that pre-legality abortion, certainly in the states, was largely - c.90% - carried out by physicians: this is what emerges from works on the reality of abortion by the likes of Mary Claderone - erstwhile medical director of Planned Parenthood - in the 60s). This is not to deny the total legitimacy of being worried about this, or of valuing women's lives. (Of course not). I'm just trying to write a little about the figures for abortion mortality.