The fullPIERS model is the tool we have to predict complications in severe pre-eclampsia (SPE). We wanted to evaluate which parameter on admission has a good predictive capacity for eclampsia, pulmonary edema, acute renal failure and perinatal death; the parameter with the greatest association was lactic acid, so we performed a logistic regression model with lactic acid and the fullPIERS model to predict these complications and add both to improve the prediction model. We also assess whether IUGR increases the risk of maternal complications. retrospective cohort of 117 maternal patients with SPE who were evaluated with laboratory and Doppler parameters at admission and until discharge. 117 patients with a diagnosis of SPE, 56 with IUGR and 61 without. The presence of renal failure was significant in the SEP plus IUGR (17.9% VS 3.3% P < 0.022), there were no significant differences in the other complications. Lactate was associated with maternal complications OR 2.3 CI 1.2-4.1, AUC 0.73 CI 0.59-0.88, p = 0.004 and with perinatal death OR 4.3 CI 1.9-9.4, p = 0.000. After that, both variables were added (lactate + fullPIERS) and a logistic regression model was performed for the FullPIERS and maternal complications with a results R2 of 2.622 (p 0.105), when the lactate was added to the previous model the R2 increased to 10.015 (p 0.007). lactic acid is a useful tool to predict maternal and fetal complications, the association of lactate to the fullPIERS model improves the discrimination capacity of the model. The presence of IUGR is associated with a higher risk of renal failure as a maternal complication. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.