Is it best to stick to diet and/or caffeine-free soda then?

Perhaps, but it is still best to not drink any sodas at all. First, they contain several chemicals, and you really ought to avoid chemicals altogether when you have a baby on the way. For example, lots of sodas contain benzene, and although it tends to be in low amounts, it is nonetheless a cancer risk. In addition, phosphoric and citric acids can wreak havoc on your teeth, causing decay and gingivitis. It’s really not worth it in the long run.

Alternatives to soda

When you’re pregnant, it is essential that you stay hydrated. Here are some recommendations:

Plain water

You should drink between 8 and 12 cups of water per day, although you should increase your water consumption even further each trimester. Ditch the mineral water though; it contains too much sodium, which in turn causes swelling.