The Infant Breast-feeding Assessment Tool (IBFAT) was used to assess the time of effective breast feeding in 48 healthy term infants born to mothers having their first or second baby. Infants of mothers who received an analgesia (butorphanol or nalbuphine) in labor (n = 26) were compared with infants whose mothers did not receive any labor analgesia (n = 22). Timing of the administration of labor analgesia was also examined with infants whose mothers received no analgesia or analgesia within an hour of birth compared with infants whose mothers received analgesia more than one hour before birth. Infants of first-time breast-feeding mothers took longer to establish effective feeding compared with infants of second-time breast-feeding mothers. Male infants also took longer. Labor analgesia significantly affected mother-rated IBFAT scores when initiation time was considered. Infants who received analgesia within an hour of birth, or no analgesia, and who initiated breast feeding early, established effective feeding significantly earlier than infants with longer duration of analgesia and later initiation of breast feeding.