Unfortunately, I know way too much about hives, albeit as a middle aged woman and not a new mother. There are lots of other drugs out there to treat hives, which are woefully misunderstood by many, including allergists. (I had one who insisted it was my 18-year-old cat and only offered a couple of drugs and then prednisone). I have yet to be on prednisone, but control with diet and some other antihistimines.  Anyway, there are many causes (and many people never know the cause) and different ways of treating them.  There is a lot of trial and error involved.  A friend of mine developed hives after her son was born and they eventually went away.
A good starting place is:
http://www.urticaria.thunderworksinc.com/   There is an email list that I have found very helpful although alternative treatments (except for diet and acupuncture) are discouraged, but some of us "talk" off list.  
Melissa Vance, JD, LLLL

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