[Study on the relation between concentration of circulating non-host fetal DNA in pregnant women and pre-eclampsia]

To explore the diagnostic value of plasma fetal DNA level in preeclampsia.

Thirty cases of pregnant women with preeclampsia (at 33 weeks and 3 days) and 30 cases of normal pregnant women (at 34 weeks and 3 days) were selected. All the pregnant women carried a male fetus by B-ultrasound, and were sampled at gestational 20 weeks, third trimester and at 1 hour, 3 hours, 6 hours after delivery. SRY levels in maternal blood were quantitated by polymerase chain reaction (QF-PCR). The endotheliotoxin (ET) level was measured with RIA.

(1) Mean fetal DNA level of patients with preeclampsia at 20 weeks of gestation was (316 +/- 61) copy/ml. They were (266 +/- 79) copy/ml, (396 +/- 91) copy/ml, (165 +/- 43) copy/ml for light and severe preeclampsia women and normal pregnant women, respectively. Maternal blood fetal DNA levels in pregnant women with preeclampsia at 20-weeks of gestation were significantly higher than those normal pregnant women (P < 0.01). (2) Mean fetal DNA level of patients with preeclampsia in third trimester was (970 +/- 413) copy/ml. They were (758 +/- 357) copy/ml, (1285 +/- 573) copy/ml, (319 +/- 99) copy/ml for light and severe preeclampsia and normal pregnant women, respectively. Maternal blood fetal DNA levels in pregnant women with preeclampsia in third trimester were significantly higher than those normal pregnant women (P < 0.01). (3) Maternal blood mean fetal DNA level of patients with preeclampsia were (139 +/- 45) copy/ml, (76 +/- 31) copy/ml, (44 +/- 13) copy/ml at 1 hour, 3 hours, and 6 hours after delivery, respectively. Mean fetal DNA level was (102 +/- 42) copy/ml, (57 +/- 25) copy/ml, (36 +/- 12) copy/ml for patients with light preeclampsia, (209 +/- 51) copy/ml, (97 +/- 40) copy/ml, (52 +/- 17) copy/ml for patients with severe preeclampsia, and (33 +/- 13) copy/ml, (9 +/- 5) copy/ml, 0 copy/ml for normal pregnant women. Significant difference was found between preeclampsia and control groups (P < 0.01). (4) The mean endotheliotoxin level for preeclampsia women was (80 +/- 18) ng/L. For light preeclampsia, severe preeclampsia and normal pregnant women ET levels were (74 +/- 14) ng/L, (89 +/- 32) ng/L, (50 +/- 11) ng/L, respectively. ET levels in pregnant women with preeclampsia were significantly higher than those normal pregnant women (P < 0.01). (5) A positive correlation was found between fetal DNA levels and ET levels in preeclampsia group (r = 0.748, P < 0.01).

The fetal DNA determination may help diagnose preeclampsia.