Association between the high soluble fms-like tyrosine kinase-1 to placental growth factor ratio and adverse outcomes in asymptomatic women with early-onset fetal growth restriction.

OBJECTIVE: To assess whether the high soluble fms-like tyrosine kinase-1 (sFlt-1) to placental growth factor (PlGF) ratio is associated with adverse outcomes (e.g., HELLP syndrome [hemolysis, elevated liver enzymes, and low platelets], severe hypertension uncontrolled by medication, non-reassuring fetal status, placental abruption, pulmonary edema, growth arrest, maternal death, or fetal death) and a shorter duration to delivery in early-onset fetal growth restriction (FGR).

METHODS: Thirty-four women with FGR diagnosed at <34.0 weeks were recruited. Serum angiogenic marker levels were estimated within 6 hours of a diagnosis of FGR. A receiver operating characteristic curve was used to determine the threshold of the sFlt-1/PlGF ratio to predict adverse outcomes. We used multivariable logistic regression analysis to examine the association between the sFlt-1/PlGF ratio and adverse outcomes. Finally, we used Kaplan-Meier analysis and the log-rank test to assess the probability of delay in delivery.

RESULTS: Women who developed adverse outcomes within a week had a significantly higher sFlt-1/PlGF ratio than did those who did not develop complications. A cutoff value of 86.2 for the sFlt-1/PlGF ratio predicted adverse outcomes, with a sensitivity and specificity of 77.8% and 80.0%, respectively. Moreover, 58.4% of women with an sFlt-1/PlGF ratio ≥86.2 versus 9.1% of those with an sFlt-1/PlGF ratio <86.2 delivered within a week of presentation (p < 0.001). In multivariate analyses, an sFlt-1/PlGF ratio ≥86.2 (adjusted odds ratio 9.52; 95% confidence interval, 1.25-72.8) was associated with adverse maternal and neonatal outcomes.

CONCLUSION: A high sFlt-1/PlGF ratio was associated with adverse outcomes and a shorter duration to delivery in early-onset FGR.