I had four last year that didn't take, they kinda went off feed but just didn't look gravid, still nice and thick, It's really hard to tell. I can see it since I've already had so many litters and have multiple animals to compare and see that difference. Not to worry if she doesn't take and you don't get babies, even the small meals will be all she needs to maintain her weight.
Think of it this way, a female that does give birth expends a huge number of calories on the babies and will need to replace those calories for her next breeding (not necessarily the next year). One that does not breed expends very few calories and can go months with no food and not lose much weight. Small meals would be all she needs to actually grow.
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Thanks,
Dave Colling

www.rainbows-r-us-reptiles.com
0.1 Wife (WC)
0.2 kids (CBB, a big part of our selective breeding program)
LOL, to many snakes to list, last count:
19.29 BRB
14.19 BCI
And those are only the breeders 
lots.lots.lots feeder mice and rats 