I had an interesting experience with Nutrasweet while breastfeeding:
My daughter had terrible gas almost since birth; she always had a
'poopy' aroma about her and passed gas almost constantly.
I eliminated almost ALL food from my diet one at a time to the
point of being down to bread only!!! No one had a clue as to the source
of the gas until someone mentioned that they got 'gassy' when consuming
aspartame. So, I eliminated it; (I was drinking about a quart of
nutrasweet koolaid a day)
Within a day or two my daughter's gassiness completely
disappeared! So, it seems that nutrasweet may well pass into the
breastmilk and have adverse effects on the infant.
I wonder, too, about prenatal exposure.....