There is a chart in one of the AWHONN books, I'm 95% sure it is this one:
AWHONN's Perinatal Nursing: Co-Published with AWHONN: Books: Kathleen Rice Simpson,Patricia A Creehan
I have a photocopy of the chart, from p.42, it is labeled "Recommended nurse to pt ratios according to the Guidelines for Perinatal Care (AAP & ACOG 1997) and the Standards and Guidelines for Professional Nursing Practice in the Care of Women and Newborns (AWHONN, 1998).
I'll try to type it:
"Intrapartum:
1:2 pts in labor
1:1 pts in 2nd stage
1:1 pts w/ med or ob complications
1:2 Pit induction or aug of labor
1:1 Coverage for initiating epidurals
1:1 circulation for c/s
Antepartum/postpartum:
1:6 antepartum or pp pts without complications
1:2 pts in postoperative recovery
1:3 antepartum or pp pts with complications but stable
1:4 recently born infants & those requiring close observation
Newborns:
1:6-8* newborns requiring only routine care
1:3-4 normal mother-newborn couplet care
1:3-4 Newborns requiring continuing care
1:2-3 Newborns requiring intermediate care
1:1-2 newborns requiring intensive care
1:1 newborns requiring multisystem support
1:1 or greater -unstable newborns requiring complex critical care
*This ratio reflects traditional newborn nursery care. If couplet care or rooming-in is used, a professional nurse who is responsible for the mother should coordinate and administer neonatal care. If direct assignment of the nurse is also made to the nursery to cover the newborn's care, there should be double assigning (ie, one nurse for the mother-baby couplet and one for just the neonate, if returned to the nursery). A nurse should be available at all times, but only one nurse may be necessary, because most neonates will not be physically present in the nrusery. Direct care of neonates in the nursery may be provided by ancillary personnel under the nurses's direct supervision. An adequate number of staff members are needed to respond to acute and emergency situations."