Tumor necrosis factor-alpha in pregnancies associated with preeclampsia or small-for-gestational-age newborns

Our purpose was to determine the presence and concentration of tumor necrosis factor-alpha in maternal and fetal plasma in pregnancies associated with preeclampsia and small-for-gestational-age newborns.

Maternal and fetal plasma tumor necrosis factor-alpha concentrations were measured in nonpregnant women (n = 12), women with normal pregnancies (n = 24), and women with pregnancies associated with severe preeclampsia (n = 23), small-for-gestational-age newborns newborns (n = 14), or both preeclampsia and small-for-gestational-age newborns (n = 12). Tumor necrosis factor-alpha was measured with a sensitive and specific enzyme immunoassay.

Tumor necrosis factor-alpha was detected in 89% of the samples studied. Concentrations ranged from < 1.5 to 30 pg/ml. Similar levels were found in women with severe preeclampsia with or without small-for-gestational-age newborns, women who were delivered vaginally or abdominally in the control group, and nonpregnant women. Maternal and fetal tumor necrosis factor-alpha in the group with idiopathic small-for-gestational-age newborns were in general lower than those of all other groups. The route of delivery did not affect tumor necrosis factor-alpha concentrations in both the maternal and fetal plasma. There was a significant correlation between fetal venous and arterial plasma concentrations (r = 0.51, p = 0.01).

Our study is the first to demonstrate a decrease in maternal and fetal plasma concentrations of tumor necrosis factor-alpha in pregnancies associated with idiopathic small-for-gestational-age newborns. This reduction may have endocrinologic importance or may reflect widespread paracrine and autocrine events. On the other hand, our findings do not support a fundamental endocrine role of tumor necrosis factor-alpha in preeclampsia.