Would this cage be sutible for a pregnant dwarf hamster?(image)?

That is way too much. Pregnant hamsters really just need to be comfortable. They also need fresh food an water every day and the bedding needs to be soft and fluffy. If you are using the shaving i say get rid of them. You might want to stick with the soft and fluffy bedding and pile it high. She will want to burrow and bury her kids until they are a certain age. You might also want to get a few extra cages depending on how many babies she has. The cage that you posted is good for them to play in but I would not buy from that brand. I hear it always falls apart and they get out. After she has had her babies you will still need to keep her very comfortable. You will want to feed her the pregnant hamster food. You will need to change her water very often. Hope i helped! A simple metal cage would be ok.