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Updated: Apr 28, 2026

Ex Vivo Perfusion of the Rodent Placenta
Published on: May 30, 2019
The effect on perioperative bleeding of placental extraction from an exteriorized uterus during caesarean section
Cheng Wei Xiao1, Allan B Climan1, Haim A Abenhaim1
1Department of Obstetrics and Gynecology, Jewish General Hospital, McGill University, Montreal QC.
Objective:
To evaluate the effect on perioperative bleeding of an alternative technique for Caesarean section, in which placental extraction is performed while the uterus is exteriorized.
Methods:
We performed a retrospective matched cohort study using data obtained through chart review. Group 1 included women who had CS performed using the technique of placental removal while the uterus was exteriorized, and group 2 included women who had CS performed using the conventional method of placental removal from a non-exteriorized uterus. Women in each group were matched for number of previous Caesarean sections, indications for CS, and gestational age. The primary outcome was the difference between preoperative and postoperative hemoglobin concentrations. Secondary outcomes included the incidence of blood transfusion, estimated blood loss (EBL), operative time, the incidence of postoperative endometritis, and length of hospital stay.
Results:
A total of 90 charts were reviewed (45 per group). Baseline clinical characteristics were similar in both groups. The mean decrease in hemoglobin concentration was 22% less in women who had placental extraction from an exteriorized uterus than in those who had the conventional placental extraction (13.2g/L vs. 16.9 g/L, P=0.016). Among secondary outcomes, women in group 1 had a lower mean EBL (531.1 mL vs. 691.1 mL, P<0.05) and a shorter mean duration of surgery (28.0 minutes vs. 40.5 minutes, P<0.05).
Conclusion:
Exteriorizing the uterus prior to removal of the placenta during CS may decrease intraoperative and immediate postoperative bleeding compared with the conventional technique. Further studies on this technique are indicated.

