Natural body hair does not generally constitute a chatzitzah unless it is matted or tangled. Thus, even a woman who usually shaves but neglects to do so before mikveh is permitted to immerse. (It is still ideal to make a habit of shaving a day or so before mikveh, rather than on the preparation day itself, so as to avoid even the suggestion of being particular about having the hair freshly shaved for immersion.) Additionally, most women are not particular about hair overlooked or inadvertently left unshaved.