There are two questions here.  1. Does breastfeeding cause increased
risk of prolactinemia?  The answer is no, and the mother does not have
to worry about a relapse of her problem.
2. Could the treatment she had interfere with her producing a full milk
supply.  The answer is quite possibly. But that is not a reason not to
start, and also not a reason not to continue if she does in fact not
seem to produce enough milk.  She can supplement with a nursing
supplementer and she can breastfeed to two years and beyond if she and
the baby both want.  There is more to breastfeeding than breastmilk.
And some breastmilk is better than none.

Jack Newman, MD, FRCPC