I’ve also heard about onion. I think it gets “tumah” or something if it’s cut up and sits overnight, unless if mixed with something else.
Fingernails should not be stepped on by a pregnant woman, so always flush them down the toilet.
Never heard about eggs…except that you shouldn’t eat them without salt…
I think that you can sleep in any direction, other than having your feet face east, and that is for married people. I heard this from somebody who asked a Rabbi, but it’s secondhand info (third now) so it’s best to ask if you really want to know…