TABLE 4

Proportion of Infants With Selected Perinatal Characteristics Admitted to NICU at 25 Weeks

Characteristic Present NICU Admitted Out of Total With Characteristic, n (%)Comparative CharacteristicNICU Admitted Out of Total With Comparative Characteristic, n (%)RRRR 95% CIP
Live birth754 of 839 (90)Stillbirth0 of 336 (0)
Maternal age, yMaternal age, y
 <2045 of 51 (88) >20709 of 788 (90)0.980.88–1.09.70
 20–34531 of 570 (93) <20 or >34223 of 269 (83)1.121.06–1.19<.001
 ≥35178 of 217 (82) <35576 of 622 (93)0.890.83–0.95<.001
Multiple pregnancy155 of 166 (93)Singleton599 of 673 (89)1.051.00–1.10.10
Breech or other289 of 322 (90)Vertex465 of 517 (90)1.000.95–1.05.93
Onset of laborOnset of labor
 Spontaneous538 of 576 (93) Nonspontaneous216 of 263 (82)1.141.07–1.21<.001
 No labor213 of 228 (93) With labor541 of 611 (89)1.061.01–1.10.04
Cesarean delivery360 of 401 (90)Vaginal delivery394 of 438 (90)1.000.95–1.04.93
Birth wt, gBirth wt, g
 <50035 of 42 (83) >500719 of 797 (90)0.920.81–1.06.15
 500–59958 of 68 (85) <500 or ≥600696 of 771 (90)0.940.85–1.05.19
 600–699126 of 140 (90) <600 or ≥700628 of 699 (90)1.000.94–1.06.96
 700–799211 of 233 (91) <700 or ≥800543 of 606 (90)1.010.96–1.06.68
 ≥800324 of 352 (92) <800430 of 487 (88)1.041.00–1.09.08
Boy409 of 456 (90)Girl345 of 383 (90)1.000.95–1.04.85
  • Denominators are total numbers of live-born infants with the indicated characteristics (from the AIHW NPDC). Numerators indicate NICU admission with the characteristic (using data from all Australian NICUs from the ANZNN data set). RR indicates the likelihood of NICU admission with a characteristic present compared with the likelihood of admission with the comparative characteristic.