Oral Presentation Society of Obstetric Medicine of Australia and New Zealand ASM 2026

Association between sFlt-1 and PlGF biomarkers at initial presentation and time to delivery in women with suspected pre-eclampsia between 20 and 36+6 weeks gestation (142079)

Rachael Grenfell-Dexter 1 , Shaun Brennecke 1 2
  1. Pregnancy Research Centre, Royal Women's Hospital - Melbourne, Melbourne, VIC, Australia
  2. Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, VIC, Australia

Background: Pre-eclampsia is a hypertensive disorder of pregnancy affecting up to 8% of pregnancies worldwide, with significant short- and long-term maternal and fetal consequences. Testing sFlt-1 and PlGF biomarkers have become integral to risk stratification and clinical decision-making in suspected pre-eclampsia. 

Aims: This study examined the association between initial sFlt-1, PlGF, and sFlt-1:PlGF ratio values and time to delivery in women with clinically suspected and subsequently confirmed pre-eclampsia between 20 and 36+6 weeks gestation.  

Methods: This was a retrospective analysis of sFlt-1 and PlGF test results from a single maternity hospital in Melbourne, Victoria between September 2016 and October 2022. Women who underwent initial pathology testing between 20 and 36+6 weeks gestation with an sFlt-1:PlGF ratio >38, indicative of elevated pre-eclampsia risk, were included (n=390). Spearman's rank correlation was used to assess associations between sFlt-1, PlGF, and the sFlt-1:PlGF ratio and time to delivery. 

Results: sFlt-1:PlGF ratio at initial testing was negatively correlated with time to delivery (R = −0.432, p < 0.001). sFlt-1 alone demonstrated a stronger correlation (R = −0.497, p < 0.001), while PlGF alone did not reach statistical significance (R = 0.114, p = 0.24).

Conclusions: Elevated sFlt-1:PlGF ratios at initial testing were associated with shorter time to delivery. Notably, sFlt-1 alone demonstrated a stronger correlation with time to delivery than the composite ratio, suggesting that PlGF contributes limited additional predictive value in this context. These findings align with evolving understanding of sFlt-1 as the more direct mediator of placental dysfunction.

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