Unlike other intestinal parasites that can migrate from mother to pups through the uterus (like roundworms), tapeworms must be contacted directly, either through fresh segments in stool, or from swallowing fleas. The pups are safe for the meantime, until they are able to swallow segments from bedding, her hair, etc.
PetSmart does carry a product called D-Worm that is supposed to be safe in pregnancy...always read the label and product inserts carefully to be sure that your pet is a good candidate for treatment.
Do be sure to pick up her stool every time she goes to prevent segments being picked up by fleas in your yard. Treating regularly for fleas is the best way to get rid of these intenstinal pests. Fleas very often migrate to a property on wild animals (squirrels, prarie dogs, mice, deer, etc.).
I do not know of any "home" remedy that I can say is going to be 100% safe for a pregnancy at this stage...I myself would err on the side of caution with new babies on the way and not try a homeopathic mix that I haven't used on any pet before.
I have been checking with a few breeder friends of mine, and they concur...you can try the D-Worm if you can find it locally, or wait for the doctor's office to get you a dose of Droncit that is right for her weight and condition.
I hope this helps you...you can try a warm (not hot) compress on her bottom just to relieve the itchy sensation temporarily.
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