PHOENIX

Pre-eclampsia in HOspital: Early iNductIon or eXpectant management

Trial started: 2014  Trial ended: 2020 

Summary

Objectives

To determine whether planned earlier initiation of delivery in women with late preterm pre-eclampsia (34+0 to 36+6 weeks' gestation) reduces maternal adverse outcomes without substantially worsening perinatal or infant outcomes, compared with expectant management.

Methods

An individually randomised, triple non-masked controlled trial with an embedded health economic evaluation conducted in 46 maternity units across England and Wales. Women with late preterm pre-eclampsia were randomised to either planned delivery or expectant management (usual care).

Outcome measures

Co-primary maternal outcome: A composite of maternal morbidity or recorded systolic blood pressure of ?160 mmHg. Co-primary short-term perinatal outcome: A composite of perinatal death or neonatal unit admission. Primary 2-year infant outcome: Neurodevelopment measured using the Parent Report of Children's Abilities–Revised (PARCA-R) composite score. Economic evaluation: Cost comparison between planned delivery and expectant management.

Results

Between 29 September 2014 and 10 December 2018, 901 women were recruited. The incidence of the co-primary maternal outcome was significantly lower in the planned delivery group than in the expectant management group (65% vs 75%; adjusted relative risk 0.86, 95% confidence interval 0.79 to 0.94; p = 0.0005). The incidence of the co-primary perinatal outcome was significantly higher in the planned delivery group than in the expectant management group (42% vs 34%; adjusted relative risk 1.26, 95% confidence interval 1.08 to 1.47; p = 0.0034), but indicators of neonatal morbidity were similar in both groups. At 2-year follow-up, the mean PARCA-R scores were within the normal developmental range in both groups (adjusted mean difference –2.4 points, 95% confidence interval –5.4 to 0.5 points; non-inferiority p = 0.147). Planned delivery was significantly cost-saving (–Ł2711, 95% confidence interval –Ł4840 to –Ł637) compared with expectant management. There were 9 serious adverse events in the planned delivery group and 12 in the expectant management group.

Conclusions

In women with late preterm pre-eclampsia, planned delivery reduces short-term maternal morbidity compared with expectant management, with more neonatal unit admissions related to prematurity but no indicators of greater short-term neonatal morbidity (such as need for respiratory support). At 2-year follow-up, around 60% of parents reported follow-up scores. Average infant development was within the normal range for both groups; the small between-group mean difference in PARCA-R scores is unlikely to be clinically important. Planned delivery was significantly cost-saving to the health service. These findings should be discussed with women with late preterm pre-eclampsia to allow shared decision-making on timing of delivery.

Adapted from: Chappell LC, Brocklehurst P, Green M, et al. Planned delivery for pre-eclampsia between 34 and 37 weeks of gestation: the PHOENIX RCT. Health Technology Assessment. 2023;27(28). https://doi.org/10.3310/CWWH0622. Licensed under the Creative Commons Attribution 4.0 International (CC BY 4.0) Licence (https://creativecommons.org/licenses/by/4.0/). Adapted for presentation on this website.