7 years after LASIK for blurry left eye. I'm pregnant now. I feel blurry vision in my left eye. Do I need to go for check up?

By all means, have an ophthalmologist examine you. It is most likely a refractive error. You won't be able to have anything done about it until after your pregnancy, however. The vision may return to normal spontaneously (by itself) after the pregnancy.

Yes, you should definitely have your eyes examined. The most common cause is a simple refractive change, but other things such as optic nerve swelling and gestational diabetes can also cause blurred vision. A simple eye exam can confirm there is nothing to be concerned about.