Evaluation of safety and performance of CentaFlow™ in the assessment of fetal growth restriction - a randomized trial and prospective cohort study.

Objectives: The aim was to evaluate the sensitivity and specificity of centaflow (CF) in a prospective multicenter study, and secondary to evaluate the safety of the CF device in a randomized multicenter study.

Methods: A sponsor-initiated multicenter randomized controlled clinical trial with termination of the randomization after enough women had been included to evaluate safety. The study proceeded as a prospective multicenter study including high-risk women (estimated fetal weight <-15 %, FGR). The first part randomized women to either standard care (SC) or SC+CF. Participants underwent CF evaluation with subsequent analysis for sensitivity and specificity for FGR at birth. Secondarily, adverse events were evaluated. Clinical assessments of fetal size conducted by midwives served as a reference. The performance of CF and SC was compared by McNemar's Test. The performance analysis of CF was done per-protocol sample.

Results: A total of 1,601 pregnant women were enrolled, with 886 undergoing CF evaluation. A total of 123 were FGR (<3rd percentile) at birth, of which 88 were evaluated by CF, and 117 had a clinical assessment of the estimated fetal weight. CF demonstrated no evidence of benefit for detecting FGR with a sensitivity of 50 % and specificity of 43 %. Adverse events associated with CF use were limited to minor skin irritation. McNemar's test showed SC was superior to CF regarding specificity as a screening tool (p=0.014).

Conclusions: While CF was safe to use, we found no evidence that CF can be used as a predictor of FGR. Further refinement of signal analysis is necessary to enhance CFs diagnostic utility.