Perhaps some of this self-doubt arises because the general public has come to view mathematics as masculine and early on women perceive themselves as being outsiders to the mathematical world. If we are to increase the number of women doctorates we will need to find methods to give them honest feedback and reassurance throughout the collegiate experience. Surprising to me is the evidence that present day women studying mathematics are extremely job oriented and a large proportion at both the bachelor's and master's level chose programs that lead directly to employment, which they then take rather than pursue further education. In this regard, they respond as first generation college graduates, although women earning mathematics degrees are generally children of college graduates having professional mothers. This is a curious finding that surely merits study.
Women respond more negatively than men to what they perceive to be poor instruction.
There is some evidence that quality of instruction is the principle factor in the decision of so many to discontinue the study of mathematics. As already noted, women need feedback on their accomplishments and not just at the end of term. They have a greater need to be recognized as individuals. Women appear to prefer discussive, discovery modes of learning and to dislike the advocacy style of many mathematics lectures. Their experience in the first two years directly effects their choice.