Table 3

Perinatal outcomes and gestational age at birth of singleton pregnancies, focusing on babies that survived

Perinatal outcomesWhole cohort (n=326)*Gestational age at PPROM (weeks+days)Unadjusted relative rate ratio of outcome for each additional week of gestation at PPROM
(RR (95% CI), P value)
16+0-17+6 (n=82)18+0-19+6 (n=102)20+0-21+6 (n=105)22+0-22+6 (n=37)
Median (IQR) gestational age at birth (weeks+days)23+0 (20+2-27+4)19+2 (17+2-27+6)21+3 (19+4-27+4)23+1 (21+2-26+6)24+2 (22+6-28+1)
Live births:
 No/total No (%) expectant management‡98/223 (44)14/43 (33)27/70 (39)37/80 (46)20/30 (67)1.25 (1.08 to 1.45), 0.004
Worst-best possible outcome (range) (minimum No/total No (%) to maximum No/total No (%)) §98/326 (30) to 201/326 (62)14/82 (17) to 53/82 (65)27/102 (26) to 59/102 (58)37/105 (35) to 62/105 (59)20/37 (54) to 27/37 (73)
Median (IQR) gestational age at birth (weeks+days)28+2 (25+2-30+2)28+4 (27+6-34+2)28+4 (26+4-30+1)27+1 (23+4-30+4)26+3 (23+1-30+1)
Survival to hospital discharge:
 No/total No (%) total expectant management†‡54/207 (26)7/40 (18)16/67 (24)21/74 (28)10/26 (38)1.19 (1.00 to 1.42), 0.06
Worst-best possible outcome (range) (minimum No/total No (%) to maximum No/total No (%)) §54/326 (17) to 173/326 (53)7/82 (9) to 49/82 (60)16/102 (16) to 51/102 (50)21/105 (20) to 52/105 (50)10/37 (27) to 21/37 (57)
Median (IQR) gestational age at birth (weeks+days)29+4 (27+1-34+2)34+2 (29+0-36+4)28+5 (27+2-33+6)30+2 (26+3-33+5)29+2 (27+6-31+1)
Survival to hospital discharge without severe morbidity:
 No/total No (%) expectant management†‡38/207 (18)5/40 (13)11/67 (16)13/74 (18)9/26 (35)1.21 (0.99 to 1.48), 0.07
 Worst-best possible outcome (range) (minimum No/total No (%) to maximum No/total No (%)) §38/326 (12) to 157/326 (48)5/82 (6) to 51/82 (62)11/102 (11) to 46/102 (45)13/105 (12) to 44/105 (42)9/37 (24) to 20/37 (54)
Median (IQR) gestational age at birth (weeks+days)30+2 (28+2-35+5)34+3 (34+2-36+4)28+5 (26+0-35+5)31+5 (28+4–35+5)30+1 (28+2-31+1)
  • CI=confidence interval; IQR=interquartile range; PPROM=preterm prelabour rupture of membranes; RR=relative rate.

  • *Gestational age at PPROM 16+0-22+6 weeks+days.

  • †Excludes pregnancies with babies that were live born at ≥22+0 weeks' gestational age with missing discharge status. PPROM: 16+0-17+6 (n=3), 18+0-19+6 (n=3), 20+0-21+6 (n=6), and 22+0-22+6 weeks’ gestation livebirth status (n=4).

  • ‡Excludes pregnancies with termination for medical reasons.

  • §Includes pregnancies with termination for medical reasons and missing discharge status.