- Effect of the oxytocin antagonist atosiban (1-deamino-2-D-tyr(OET)-4-thr-8-orn-vasotocin/oxytocin) on nocturanl myometrial contractions, maternal cardiovascular function, transplacental passage, and fetal oxygenation in the pregnant baboon during the last third of gestation. Nathanielsz, P.W., Honnebier, M.B., Mecenas, C., Jenkins, S.L., Holland, M.L., Demarest, K. Biol. Reprod. (1997)