Epinephrine and Pregnancy

Epinephrine, by β1-adrenergic activity may decrease uterine contraction and prolong labor; and by α1-adrenergic activity may decrease uterine blood flow and fetal circulation. However, it has been shown that bolus doses epinephrine, 0.1 mg, did not prolonged the duration of labor and did not adversely affect placental blood flow and fetal circulation.66-77 It is of note that investigators considered the addition of epinephrine to LAs beneficial for it reduced the dosage of LA required for pain relief.