OXT and pulmonary arterial hypertension: Only three studies reported the rates of postpartum hemorrhage (PPH) [14, 15, 18], one showed no differences in its rate (6.4% vs 6.3% [18]) and the other two showed a decrease in the PPH rates in the discontinuous oxytocin group without reaching statistical significance, probably due to a lack of power (16% vs 22% [14] and 1.4% vs 3% [15]).