Be careful of any medication during pregnancy. Most of the medication are made of chemical things, even if they can ease your trouble such as red eyes, itching eyes or other eye diseases, they may also cause other effect to your body. You'd better go to check and ask for your obstetrician for suggestions or let them to prescribe medicine/eye drops for you.
It depends on whether the eyedrops contain medications. If they have any kind of medications, then you should check with your doctor to see whether you can use them during pregnant. If they are only used to wet your eye, then they are safe to use during your pregnant.