Changes over time in attitudes to treatment and survival rates for extremely preterm infants (23-27 weeks' gestational age).

We determined the changes over time in attitude to treatment of very preterm infants (23-27 weeks of gestational age) born at the Royal Women's Hospital, Melbourne, and their survival rate. The subjects were consecutive livebirths at 23-27 weeks' gestational age born from 1983-1994, inclusive. The main outcomes measured were the proportions of livebirths treated intensively and survival rates to hospital discharge, both excluding lethal abnormalities. Over the 12 years of the study there were 788 livebirths free of lethal abnormalities born at 23-27 week's gestational age. Overall 669 (85%) were treated intensively; the proportions treated intensively rose significantly over time from 74% in 1983-1985 to 91% in 1992-1994, and with increasing gestational age, from 19% at 23 weeks to 100% at 27 weeks. Overall 439 (56%) survived their primary hospitalization; the survival rate rose significantly over time, from 43% in 1983-1985 to 70% in 1992-1994, and with increasing gestational age, from 3% at 23 weeks to 78% at 27 weeks. In 1992-1994, the survival rates were 11% at 23 weeks, 53% at 24 weeks, 70% at 25 weeks, 81% at 26 weeks, and 87% at 27 weeks. For infants treated intensively, the survival rate rose significantly from 53% in 1983-1985 to 76% in 1992-1994, The largest increases in survival have occurred in the 1990s, and at 24 and 25 weeks' gestational age. The proportions of very preterm infants treated intensively and their survival rates have increased over time, and have always been higher with increasing gestational age.