Objective: Our purpose is to investigate if tumor necrosis factor-∝(TNF-∝) levels in midtrimester correlate with pregnancies complicated by preterm labor, preeclamsia, and intr- auterine growth retardation(IUGR). Study Design: A case control study design was used to compare midtrimester amniotic fluid TNF-∝ levels from women with normal pregnancy outcome(n=54) and pregnancies complicated by preterm labor(n=10), preeclampsia(n=8), and IUGR(n=4). Result: TNF-∝ levels in midtrimester amniotic fluid in women with normal pregnancy ourcome were 8.8±4.0pg/ml. Also, TNF-∝ levels in women with preterm labor, preeclamsia, and IUGR were 9.7±6.0pg/ml, 6.0±4.1pg/ml, 7.5±2.6pg/ml respectively. Conclusion: TNF-∝ levels in midtrimester amniotic fluid do not correlate with preg- nancies complicated by preterm labor, preeclamsia, and IUGR different from the third trime- ster(p=0.06).