Does preeclamptic pregnancy increase fetal-maternal hemorrhage?

Association of placental inflammation with fetomaternal hemorrhage and loss of placental mucin-1

BACKGROUND

Fetomaternal hemorrhage (FMH) poses an immediate risk to the fetus and, in case of Rhesus-immunization, to future pregnancies. Given that altered endothelial permeability is part of the pathophysiology of inflammation, in this study we investigated whether placental inflammatory processes like chorioamnionitis (ChoA) or preeclampsia (PE) lead to increased rates of FMH compared to the established risk factor of placenta previa (PP). Putative accompanying markers of trophoblastic damage were also explored.

METHODS

40 patients (14 PE; 6 ChoA; 9 PP; 11 normal controls) were evaluated for FMH using a flowcytometric test kit, which is able to quantify FMH of 0.06% fetal cells. Placental tissue samples were immunostained for human placental lactogen (hPL), human chorionic gonadotropin (hCG), and mucin-1 (MUC1). MUC1 was evaluated as a potential serum marker of FMH.

RESULTS

Patients with ChoA had a mean calculated FMH volume of 29 ml, compared to 4 ml in PE and 1 ml in PP and controls. MUC1 staining was reduced in PE and ChoA placenta samples, while elevated MUC1 serum concentration correlated positively with FMH.

CONCLUSION

Diseases of placental inflammation are associated with FMH. Placental MUC1 staining is reduced and serum concentrations are increased in cases of FMH.

Is the incidence of fetal-to-maternal hemorrhage increased in patients with third-trimester bleeding?

OBJECTIVE

If a pregnancy is complicated by third-trimester bleeding, is there a higher risk of fetal-to-maternal hemorrhage that might necessitate the administration of additional anti-D immune globulin to prevent alloimmunization in the patient who is Rh D-negative? The study objective was to analyze prospectively the incidence of fetal-to-maternal hemorrhage in pregnancies that were complicated by third trimester bleeding compared with three control groups.

STUDY DESIGN

Pregnancies that were complicated by third-trimester bleeding, preterm premature rupture of the membranes, and preterm labor were identified prospectively on admission. A group of preterm patients with no complications was also collected prospectively. Patients with any history and/or clinical evidence of trauma were excluded. Kleihauer-Betke tests were performed with all patients, and the results were blinded until study completion. Sample size calculations were performed to determine the minimum number of cases needed in each group.

RESULTS

A total of 403 patients were collected during the study period: 91 patients had third-trimester bleeding, 101 patients had preterm premature rupture of the membranes, 116 patients had preterm labor, and 95 patients were in the no complication group. There was no statistical difference identified in the Kleihauer-Betke test results between any of the study groups.

CONCLUSION

The incidence of fetal-to-maternal hemorrhage does not appear to be increased in pregnancies that are complicated by third-trimester bleeding when compared to noncomplicated control subjects or to other obstetrically complicated pregnancies. This information would suggest that the routine administration of additional anti-D immune globulin (beyond the current recommended protocol) to women who are Rh D-negative whose pregnancies are complicated by third-trimester bleeding is not indicated.