Breakfast meal replacements during pregnancy?

Has anyone asked their OB or a nutritionist about drinking meal replacement smoothies (like Boost or Ensure) during pregnancy? I have a hard time eating in the morning, but as soon as I get something in my stomach, my nausea goes away. That being said, mornings where I work early are very difficult, being that it is hard to find something easy to eat that I can eat while working, that is also nutritionally beneficial. I wind up eating a lot of bagels or dry cereal. A nutritionally rich meal replacement would be ideal for working mornings.

Are those healthy/beneficial for pregnancy?

Thanks!