Supplementary Material for: sFlt-1/PlGF ratio at 24 weeks gestation in twin pregnancies as a predictor of preeclampsia or fetal growth restriction

Objective: to elucidate if sFlt-1/PlGF ratio at 24 weeks in twin pregnancies could be useful to select patients who subsequently develop diseases related to placental dysfunction, such as preeclampsia or fetal growth restriction (FGR). Methods: prospective study among all twin pregnancies followed up at a tertiary Hospital. The sFlt-1/PlGF ratio was determined at 24 weeks. Results: a total of 108 patients with a twin gestation were included. Pregnant women who developed preeclampsia and/or FGR displayed a significantly higher sFlt-1/PlGF ratio at 24 weeks, compared to those who did not develop these diseases (20.3 vs 4.3, p=0.002). Mean sFlt-1/PlGF ratio was not significantly different between patients who subsequently developed preeclampsia compared with those that developed FGR (29.8 vs 18.45, p=0.42). An sFlt-1/PlGF ratio ≥17 at 24 weeks is associated with a significant increase in the frequency of preeclampsia (odds ratio, 37.13 [95% confidence interval, 4.78–288.25]; p=0.002), and FGR (odds ratio, 39.58 [95% confidence interval, 6.31–248.17]; p<0.001). The addition of maternal characteristics, and mean pulsatility index of the uterine arteries to the sFlt-1/PlGF ratio at 24 weeks enhance the identification of patients who develop preeclampsia or FGR. Conclusion: sFlt-1/PlGF ratio at 24 weeks in twin pregnancies, combined with mean pulsatility index of the uterine arteries and maternal characteristics, could select patients who develop preeclampsia or FGR. These patients might benefit from a close follow-up in order to avoid maternal-fetal adverse outcomes.