I am fortunate to work in a hospital with 3200 annual births,that has been
fairly successful moving away from nursery usage. Babies are admitted at the
mothers bedside.  All care is given in the mothers room, including pediatric
exams, baby photos, and lab tests. We routinely do skin to skin after birth
and have babies breastfeed soon after birth.

The baby holding room is only used for circumcisions and at night.  We still
struggle with mothers requesting babies be taken out of their room at night
(even though we have all private rooms, with sleeping space for the
significant other in the mothers room and encourage co sleeping).

I am responsible for our unit budget and I can explain what the nursery
charge is when the baby isn't using the nusery.

The nursery charge WILL typically show up in hospitals who do not use a
nursery. Why?  Because it is actually the room charge, just like the mothers
room charge. Because of reporting requirements newborns can not be included
in the daily hospital census, thus they are listed in the "nursery" instead
of room number xxx.

The room charge (listed as either nursery or room charge) is charged to pay
for all the supplies used by the baby (linen, exam supplies, diapers, etc),
the nursing care and the hospital overhead (staff education, lighting,
heating, furniture, equipment, administration, anxillary departments, etc).

What nursing care?  Nurses teach, nuture and help the mother with the baby
in her room (especially with more breastfeeding!).  The nurses are also
required by Joint Commission (the hospital accrediting organization) to
chart on the baby and provide all the same assessments and care as if the
baby was in a nursery. The hospital also hires staff to do the required
documents (birth certificates, PKU reports, paternity declarations, etc).

The same amount of nurses are needed to care for mothers and babies, no
matter if there is a nursery or not. The typical mother baby  couplet
assignment is 4 (or 8 total patients).  In the traditional model the nursery
nurse would have 8 babies and the OB nurse 8 mothers.

So encourage mothers to check their bills, but understand that a nursery
charge may simply be the "room charge" for the baby while being in the
hospital.