Two-year follow-up of infant and maternal outcomes after planned early delivery or expectant management for late preterm pre-eclampsia (PHOENIX): a randomised controlled trial

Abstract

OBJECTIVE: We evaluated the best time to initiate delivery in late preterm pre-eclampsia in order to optimise long-term infant and maternal outcomes. DESIGN: Parallel-group, non-masked, randomised controlled trial SETTING: 46 UK maternity units POPULATION: Women with pre-eclampsia between 34+0 and 36+6 weeks' gestation, without severe disease, were randomised to planned delivery or expectant management. PRIMARY LONG-TERM OUTCOME: Infant neurodevelopmental outcome at 2 years of age, using the PARCA-R (Parent Report of Children's Abilities-Revised) composite score. RESULTS: Between Sept 29, 2014, and Dec 10, 2018, 901 women were enrolled in the trial, with 450 allocated to planned delivery and 451 to expectant management. At 2-year follow-up, the intention-to-treat analysis population included 276 women (290 infants) allocated to planned delivery and 251 women (256 infants) to expectant management. The mean composite standardised PARCA-R scores were 89.5 (standard deviation (SD) 18.2) in the planned delivery group and 91.9 (SD 18.4) in the expectant management group, with an adjusted mean difference of -2.4 (95% CI -5.4 to 0.5) points. CONCLUSION: In infants of women with late preterm pre-eclampsia, average neurodevelopmental assessment at 2 years lies within the normal range, regardless of whether planned delivery or expectant management is pursued. Because of lower than anticipated follow-up, there was limited power to demonstrate these scores were not different, but the small between-group difference in PARCA-R scores is unlikely to be clinically important