Well there is obviously no male in the cage with her, because IF you had a male and female together I would suggest removing the male because when a female hampster gives birth, the male immediately impregnates her again, lol.

Umm... really no advice to give... leave them in a quiet room that doesn't get a lot of traffic, DO NOT DISTURB THE MAMMA OR THE BABIES except for feeding, don't pick up or handle the babies... don't leave the cage in a drafty area... of course these are all obvious tips for owning a hampster in general not just a pregnant female or babies.

Oh when they get old enough you NEED to separate them, but that won't be for a few months. It's not wise to cage two adult hampsters in a cage together because they will fight. As babies they get along but as they get older they get terribly territorial.