Neonatal survival rates in 860 singleton live births at 24 and 25 weeks gestational age. A Canadian multicentre study.
OBJECTIVE
To determine the current survival rate of singleton living newborns born at gestational age of 24 and 25 weeks, using obstetric factors available to the physician before birth.


METHODS
Retrospective study of all live births in 13 of 17 Canadian tertiary centres. Population All singleton live births without congenital abnormalities.


METHODS
During the years 1991-1996, data were abstracted from clinical databases and charts of 860 live births, in 13 of the 17 tertiary centres in Canada, all with major neonatal intensive care units. Newborn survival was defined as alive at discharge from neonatal intensive care unit. Abstracted elements included gestational age, maternal antenatal corticosteroid treatment, birthweight, gender, fetal presentation and mode of delivery.


RESULTS
Average survival rates increased from 56.1% at 24 weeks (n = 406) to 68.0% at 25 weeks (n = 454). Survival rates ranged from 53.1% at day 168 to 81.6% at day 181 (r = 0.802, P < 0.05). Steroid administration improved the survival rates at 24 and 25 weeks compared with that of unexposed fetuses, respectively (58.9% vs 41.8%; OR 1.70; 95% CI 1.03-2.08 and 74.2% vs 56.8%; OR 2.19; 95% CI 1.41-3.38). Caesarean delivery for breech presentation improved survival compared with vaginal delivery, both at 24 and 25 weeks (56.1% vs 36.0%; OR 2.19; 95% CI 1.10-4.34, and 68.7% vs 55.2% OR 1.78; 95% CI 0.093-3.43). Female neonates displayed better survival rates (59.6% vs 52.1% OR 1.36; 95% CI 0.92-2.01, and 72.6% vs 63.1% OR 1.51; 95% CI 1.02-2.25) at 24 and 25 weeks, respectively. Explanatory regression model confirmed these factors as prognostic variables associated with survival.


CONCLUSIONS
This extensive collaborative study confirms that several prognostic factors, known before birth, including gestational age in days, steroid treatment, mode of presentation and fetal sex may help obstetricians, neonatologists and parents in their decision-making process at 24 and 25 weeks of pregnancy.
British Columbia Women's Hospital, Vancouver, Canada.
Sidney B
SB
Effer
Jean-Marie
JM
Moutquin
Dan
D
Farine
Saroj
S
Saigal
Carl
C
Nimrod
Edmond
E
Kelly
Theophile
T
Niyonsenga
D000293:Adolescent; D001724:Birth Weight; D002170:Canada / Q000453:epidemiology; D005260:Female; D005865:Gestational Age; D006801:Humans; D007226:Infant Mortality; D007231:Infant, Newborn; D007234:Infant, Premature; D007746:Labor Presentation; D016015:Logistic Models; D011247:Pregnancy; D011379:Prognosis; D012044:Regression Analysis; D012189:Retrospective Studies; D015996:Survival Rate