Prophylactic intramyometrial carboprost tromethamine does not substantially reduce blood loss relative to intramyometrial oxytocin at routine cesarean section.

The influence of intramyometrial injection of 125 micrograms of 15-s-15-methyl prostaglandin F2 alpha (carboprost tromethamine, Prostin/15M) versus 20 U of oxytocin immediately after delivery of placenta on blood loss at cesarean section was investigated by means of a double-blinded, randomized trial. Hematocrit decrease from the day before operation to the third postoperative day was used as an index of blood loss. Decreases in hematocrit were comparable for the oxytocin and carboprost tromethamine groups. Excess blood loss (hematocrit decrease more than 6 vol. %) was significantly associated with the indication for cesarean section (three of four for cephalopelvic disproportion versus 9 of 42 others, p less than 0.01), but not with age, parity, number of prior cesarean sections, or birthweight. Carboprost tromethamine does not appear to be more effective than oxytocin when given by intramyometrial injection at this dose for routine cesarean section; its prophylactic utility in higher doses or in cases at risk for hemorrhage from uterine atony remains to be investigated.