Low‐Dose Aspirin in the Prevention of Recurrent Spontaneous Preterm Birth Stratified by Placental Maternal Vascular Malperfusion: Secondary Analysis of a Randomized Trial
James A. L. Meliëzer, Anadeijda J. E. M. C. Landman, Adelia A. Gieskes, Marianna Bugiani, Laura Visser, Mireille N. Bekker, Judith O. E. H. van Laar, Marieke Sueters, Sanne J. Gordijn, Joris van Drongelen, J. Marko Sikkema, Wietske Hermes, Anjoke J. M. Huisjes, Dimitri N. M. Papatsonis, Janine Boon, Joost J. Zwart, Christianne J. M. de Groot, Martijn A. Oudijk, Marjon A. de BoerABSTRACT
Objective
To evaluate the effectiveness of low‐dose aspirin in the prevention of recurrent preterm birth (PTB) in women with signs of maternal vascular malperfusion (MVM) in the placenta of the previous spontaneous PTB.
Design
Secondary analysis of the APRIL study.
Setting
The APRIL study, conducted in 34 centres in the Netherlands, evaluated low‐dose aspirin versus placebo in the prevention of recurrent PTB after spontaneous PTB.
Population
Women with a history of spontaneous PTB participating in the APRIL study, with available placenta histology reports from the previous spontaneous PTB.
Methods
Placental histology reports were retrieved from participating centres and categorized for presence of MVM as defined by the Amsterdam criteria.
Main Outcome Measures
Recurrent PTB.
Results
Placental histology reports of the previous spontaneous PTB were available for 41.3% (160/387) of participants, and MVM was present in 27.5% (44/160). In participants with MVM, recurrent PTB occurred in 4.2% (1/24) of the aspirin group, versus in 45.0% (9/20) in the placebo group (Relative Risk (RR) 0.09; 95% Confidence Interval (CI) 0.01–0.43; p = 0.02). In participants without MVM, PTB occurred in 29.3% (17/58) in the aspirin group compared to 17.2% (10/58) in the placebo group (RR 1.70; 95% CI 0.87–3.56; p = 0.13).
Conclusion
In women with a history of spontaneous PTB and signs of MVM in the placenta, a vascular‐mediated subgroup, the use of low‐dose aspirin in a subsequent pregnancy was associated with a lower rate of recurrent PTB.