Well you could:
1. Leave them, she'll probably eat many if not all of them.
2. take the mother out as soon as she gives birth (assuming you've got another tank for her)
3. Use a gravel siphon and "suck" the fry out into a bucket (to be transplanted into a fry growout tank, assuming you've got one)
4. If no other tanks are available you could try putting a whole bunch of "caves/hides" for the fry to escape into to avoid mommy, obviously with holes small enough for her to not enter.
Obviously there are ways to do all of this "properly" using breeding nets/cages etc. but it's not worth the investment IMO unless you intend to breed them as a hobby.