Yes, you can get eye checked during pregnancy. If you have poor vision, you can buy a pair prescribed glasses temporarily. After you give birth to your baby, you'd better get another eye check again and buy another new prescription eyeglasses. This is because your prescription is likely changes during pregnancy and it will recover after you give birth to the baby. This is a common and normal phenomenon for people pregnant.
You'd better not have an eye exam during pregnant, otherwise it will cause effect on your baby. During pregnant, your prescription is changing, so you don't have to get a new pair of eyeglasses because your vision will return to normal after pregnancy. Besides, if you go to have an eye exam, the doctor will prescrible some medicines or eye drops for you to dilate your pupils so that he can check your eyes easily. These medicines may cause side effect on your baby.
Yes,you can. By the way, I should remain you that your prescription is changing when you are pregnant but it will return into normal again after pregnancy. So it is not an urgent case. If you really want to have a check of your eyes, you are suggested to just have it not to take the prescribed medicines.