Possibilities could be because shes afraid of having a relationship with her child like her mother did with her or that her pregnancy forces her into isolation because she cant tell anyone. I believe though that the reason she wants an abortion is because if she has the child Dewey feels like its anchoring her into her poor social class. A single mother at that time would have little chance of getting married not only to someone of a higher class but even in the same class. In Coletta Brown's Motherhood Is Powerless she writes about how motherhood is powerless for women and after reading this story I saw a lot of Dewey Dell relating to this. Brown describes her own struggle with children and how she quit graduate school and just struggled in life generally with a child to look after. She refers to her motherhood as "My days were dominated by a totally dependent creature's needs. "(52.). Coletta Brown's message throughout the article is not directly related to Dewey but the overall message that women need to be able to take care of themselves before entering motherhood is. Dewey Dell's want from an abortion comes from the same fear that if she has this child she will be forever stuck in her low social class with no hope of ever escaping it. She will have no time nor the resources to better herself but only take care of her child.
Only those from low social classes have strong beliefs in religion. Since they will never have the greater materialistic things they believe that their faith supersedes the material. Religion makes social class irrelevant and thats why people from a lower social class gravitate toward it. The Bundren family seems to have a strong belief in religion although they have different uses for it. Anse uses religion not to serve a higher power but for uses religion to suit him. A good example of this is when he says "Nowhere in this sinful world can an honest, hardworking man profit.