I don’t have time this morn to comment on the study or the findings, but I thought I’d link to an article (which contains a link to the original study) for those of you who want to dig into the materials.
Researchers found 40% of these women mentioning something financial, 36% in some way discussing the bad “timing” of the pregnancy, 31% raising a partner issue, 29% speaking of “other children,” 20% talking of the child somehow interfering with future opportunities.
Less than 20% mentioned something about not being emotionally or mentally prepared (19%), health related reasons (12%), wanting a better life than she could provide (12%), not being independent or mature enough (7%), influence of family or friends, and not wanting to have a baby or to place a baby up for adoption (4%). 
These do not add to 100%, of course, because women tended to give more than one reason. And some other important qualifications need to be made to give a proper analysis
Looking more carefully at the data
These responses reflect a women’s self-reported subjective assessment, not some independent analysis of her situation. As such, it is a good guide to her perceptions (or at least to her beliefs about what others will consider an acceptable justification). But they do not necessarily tell us the facts about her circumstances.
For example, though we know from demographic data reported by the authors that 45% of women participating in the survey were receiving public assistance and that a considerable portion (40%) were not able to indicate that they had “enough money in the past month to meet basic needs,” we do not know what these women’s precise income was or what mix of public and private resources were available in their communities.
Would they have arrived at the same conclusion if someone had sat down with them, looked at the sort of resources available to them, and given them the sort of budget planning advice and assistance that is available at many local pregnancy care centers?