Objective: To investigate the placental CD34, CD44, and leukemia inhibitory factor (LIF) levels in normotensive and pre-eclamptic women. Method: The study population consisted of 21 women with pre-eclampsia. Twenty normotensive pregnant women served as controls and were matched to pre-eclamptic patients by gestational age at delivery. Decidual samples obtained from the central part of the placenta were stored at -70 degrees C until analysis. CD44 and LIF were quantified in homogenates by enzyme-linked immunosorbent assay (ELISA), while CD34 was quantified by flow cytometry. Results: The pre-eclamptic and normotensive groups were well matched. There were no significant differences in age, parity, weight, and gestational age at birth between the groups (P>0.05). The mean placental levels of CD34 (6.55 +/- 2.48 vs 3.16 +/- 1.23), CD44 (385.24 +/- 178.85 vs 157.75 +/- 31.73, and LIF (140 +/- 51.11 vs 96.25 +/- 31.62) were significantly higher in pre-eclamptic compared with normotensive women, respectively (P<0.05). Conclusion: Higher levels of CD34, CD44, and LIF were found in the placentas of pre-eclamptic compared with normotensive women. (c) 2007 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.