As shown in Fig. 3, plasma levels of TNF-α and VEGF in severe preeclampsia group were significantly increased as compared with normal pregnancy group (585.5 ± 38.5 pg/ml and 308.5 ± 141.3 pg/ml vs. 1.4 ± 17.5 pg/ml and 174.8 ± 61.5 pg/ml, p < 0.001 and p < 0.01), and these levels showed an increasing trend with the grade of retinopathy. This evidence concerns the gene TNF and preeclampsia.