In pre-eclampsia, poor placentation causes both oxidative and endoplasmic reticulum stress of the placenta. The anti-oxidative protein Haptoglobin has three phenotypes: 1-1, 1-2, and 2-2. Haptoglobin 1-1 is a more potent antioxidant. Our objective was to determine whether haptoglobin 1-1 was less common in women with preeclampsia which is a disease with an oxidatives-stress component, compared to the healthy population. Haptoglobin phenotype was compared in 240 healthy and 120 preeclamptic gravida in a case-control study. Statistical analysis was performed using Chi square test. The prevalence of haptoglobin 1-1 was 13% among healthy women and 6% among preeclamptic women (P=0.049). Secondary analysis was also performed. The prevalence of haptoglobin 1-1 is higher in healthy compared to preeclamptic subjects, a finding compatible with a protective role. Haptoglobin 1-1 might have a protective role in preeclampsia. Further work is needed with more Hp 1-1 subjects before we can conclude on the possible use of Haptoglobin phenotype to assess the risk of preeclampsia.