be prepared to get an extra cage just incase she and the other degu start fighting alot, seeing as if she is pregnant it might cause her to lose some of the babies. she will need someplace to bring the babies that she thinks is safe enough (about 75 degrees F, and somewhat dark).
She will want to bring some kind of hammock or fabric tunnel that you have into there probably, so it would be a good idea to take an old shirt and cut out a big square (8x8 to 10x10)
Other than that it just comes down to not holding her a whole ton and try not letting her run on her wheel quite as much as normal. ALSO remember to move the babies to the lowest level if she gives birth on an upper floor. we dont want any falls now
best of luck