RESUMEN
OBJECTIVE: To investigate associations of the Fetal Pillow® with maternal and neonatal morbidity. DESIGN: Retrospective cohort. SETTING: Two tertiary maternity units, New Zealand. POPULATION OR SAMPLE: Full dilatation singleton, term, cephalic caesarean section, with three comparisons: at Unit A (1) before versus after introduction of the Fetal Pillow® (1 Jaunary 2016-31 October 2021); (2) with versus without the Fetal Pillow® after introduction (27 July 2017-31 October 2021); and (3) between Unit A and Unit B during the same time period (1 January 2019-31 October 2021). The Fetal Pillow® is unavailable at Unit B. METHODS: Cases were ascertained and clinical data were extracted from electronic clinical databases and records. Outcome data were adjusted and presented as adjusted odds ratios (aOR) with 95% CI. MAIN OUTCOME MEASURES: Primary outcome "any" uterine incision extension; secondary outcomes included major extension (into adjacent structures), and a composite neonatal outcome. RESULTS: In all, 1703 caesareans were included; 375 with the device and 1328 without. Uterine incision extension rates were: at Unit A before versus after introduction: 26.8% versus 24.8% (aOR 0.88, 95% CI 0.65-1.19); at Unit A with the Fetal Pillow® versus without: 26.1% versus 23.8% (aOR 1.14, 95% CI 0.83-1.57); and at Unit A versus Unit B: 24.2% versus 29.2% (aOR 0.73, 95% CI 0.54-0.99). No differences were found in major extensions, or neonatal composite outcome. CONCLUSIONS: Despite the relatively large size of this study, it could not rule out either a positive or a negative association between use of the Fetal Pillow® and uterine extensions, major uterine incision extensions, and neonatal morbidity. Randomised controlled trial evidence is required to assess efficacy.