The aim of this study was the analysis of the umbilical cord serum sHLA-G levels in pregnancies complicated by severe preeclampsia and/or IUGR. Patients and Methods. The study was carried out on 12 preeclamptic patients with appropriate-for-gestational-age weight infants, 14 pregnant patients with severe preeclampsia complicated by IUGR, 7 normotensive patients with isolated IUGR, and 22 healthy controls with uncomplicated pregnancies. Results. Our study revealed higher umbilical serum levels of sHLA-G in preeclamptic pregnancies complicated by IUGR and decreased in the preeclamptic women with the normal fetal growth. The pregnant normotensive patients with isolated IUGR revealed the same levels of sHLA-G as observed in healthy pregnant controls. Conclusions. Lower levels of sHLA-G observed in preeclamptic pregnancies without IUGR may lead to excessive maternal immune reaction against the fetus. Higher levels of sHLA-G in preeclamptic pregnancies with IUGR may reflect the excessive releasing of this molecule to protect fetus, but it may be insufficient to balance disturbed fetomaternal immune relationship. The lack of association with normotensive pregnancies complicated by isolated IUGR may suggest that a different pathomechanism is involved in the impairment of intrauterine fetal growth in both patient groups with pregnancies complicated by isolated IUGR and in the course of preeclampsia.