Oxytocin

Sir Henry H. Dale first identified oxytocin and its uterine contractile properties in 1906. Like all other neurohypophysial hormones, oxytocin is composed of nine amino acids with a disulfide bridge between the Cys 1 and 6 residues. In the mid-1950s, synthetic oxytocin was successfully synthesized by a biochemist named Vincent du Vigneaud; he was later recognized with a Nobel prize for his work. Oxytocin continues to be an important tool in modern obstetrics to induce labor when indicated and to manage postpartum hemorrhage. It is estimated that labor induction with oxytocin is used in almost 10% of deliveries globally.

It should be noted that there are risks associated with oxytocin intervention during childbirth. Oxytocin should be used judiciously only when necessary and by experienced healthcare practitioners.

Although most commonly linked to labor and delivery, oxytocin actually has broad peripheral and central effects. It plays an important role in pair bonding, social cognition and functioning, and even fear conditioning. Oxytocin also serves a role in metabolic homeostasis and cardiovascular regulation.

Administration of exogenous oxytocin is indicated in the antepartum period to initiate or improve uterine contractions for vaginal delivery in situations where there is fetal or maternal concern. For example, It may be used to induce labor in cases of Rh sensitization, maternal diabetes, preeclampsia at or near term, and when delivery is indicated due to prematurely ruptured membranes. Importantly, oxytocin is not approved or indicated for elective induction of labor. Oxytocin may be used to reinforce labor in select cases of uterine inertia and as adjunctive therapy in the management of incomplete or inevitable abortion. In the postpartum period, oxytocin may be used to induced contractions in the 3rd stage of labor and to control postpartum bleeding or hemorrhage.