Many preschoolers regularly see their parents completely or partially nude—either coming out of the shower, getting dressed, or using the toilet. Yet some parents feel uncomfortable about exposing their children to their naked bodies.
It won't do your child any harm to see you naked as long as you remain relaxed and comfortable about your nakedness. Modeling comfort with (or even pride in) your naked body is not at all a bad thing for your child. After all, you want her to feel comfortable and proud about her body too, don't you?
If you don't feel comfortable being naked in front of your preschooler then don't feel obligated to do so. In fact, if anyone in your household (you, your partner, or your child) feels uncomfortable with nudity, then it only makes sense to respect and consider his or her feelings and cover yourself up. Your child can find out about the differences between male and female anatomy or the anatomy of children and adults in many other ways.
If your nudity prompts your child to ask questions about the different size and shape and hairiness of his or her genitalia compared to yours, reassure your preschooler that all the parts of the body will grow and change as he or she does. A comparison with adult genitalia may make your child feel somewhat inadequate. To avoid this, you'll need to reassure your child that his or her genitalia are just the right size and shape for now—and will be just the right size and shape when he or she grows up, too.