First-trimester placental growth factor (PlGF) and HELLP syndrome: the PREDICTION study

OBJECTIVE: Hemolysis, elevated liver enzymes and low platelets (HELLP) syndrome is a complication of preeclampsia. We aimed to estimate the association between first-trimester placental growth factor (PlGF) and other preeclampsia risk factors with HELLP syndrome. METHODS: We performed a secondary analysis of a prospective cohort of nulliparous women recruited at 11-14 weeks of gestation and stratified according to pregnancy outcome: HELLP syndrome, preeclampsia without HELLP syndrome, or neither (controls). We compared the three groups for first-trimester maternal age, body mass index (BMI), mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI) and serum PlGF in multiples of the median (MoM), using non-parametric and ROC curve analyses. RESULTS: Of the 7325 eligible participants, 27 (0.4%) developed HELLP syndrome and 228 (3.1%) developed preeclampsia without HELLP. Median PlGF was lower in the preeclampsia (median: 0.85 MoM; IQR: 0.61-1.15; P < 0.001), and HELLP syndrome (0.72 MoM; IQR: 0.55-1.09, P < 0.001) groups, compared to controls (1.02 MoM; IQR: 0.72-1.43). At PlGF≤0.7 MoM the prediction rate for preterm and term HELLP was 56% and 33%, respectively, and the respective values for preeclampsia without HELLP were 50% and 30%, respectively, at a false positive rate of 17%. In HELLP syndrome, unlike preeclampsia without HELLP, there was no association with first-trimester BMI, MAP or UtA-PI. CONCLUSION: At 11-13 weeks, low PlGF was the only factor associated with HELLP syndrome.