Effect of maternal heme degradation on fetal carboxyhemoglobin concentration in pregnancy-induced hypertension

The adverse effect on fetal hemogram by preeclampsia: marked anisocytosis with normocytic, normochromic erythrocythemia as well as thrombocytopenia

Whether preeclampsia affects the fetal hematologic system still remains a controversial issue. The purpose of this series was to examine the hypothesis that preeclampsia may or may not cause adverse effects on fetal hemogram, including erythrocytes, leukocytes, and platelets. In addition, no one, to date, has reported the effect on red cell distribution width (RDW) of fetal cord blood by preeclampsia. Therefore this series also tested the hypothesis that preeclampsia may induce elevation of RDW in fetal cord blood. From August 1, 1989 to July 31 1990, we prospectively collected cord blood samples at parturition from 21 preeclamptic pregnancies and 366 uncomplicated controls and measured their complete blood counts by computerized blood autoanalyzer. The results of the comparison with red blood cells showed significant erythrocythemia (P < 0.05), increased hematocrit (P < 0.05), elevated hemoglobin (P < 0.05), and marked anisocytosis (as reflected by RDW, P < 0.0001) in preeclamptic pregnancies than in controls. Though no significant differences were demonstrated in the white cell counts, severe thrombocytopenia (P < 0.001) was observed in the preeclamptic group than in controls. We concluded that preeclampsia may cause significant normocytic, normochromic erythrocythemia, marked anisocytosis and severe thrombocytopenia in newborns, which deserved the attention of obstetricians and neonatologists. Further studies are warranted to elucidate the underlying pathophysiological mechanisms.