Objective: To compare the efficacy of atosiban with usual management of threatened preterm labor.
Methods: In this prospective, open-label, randomized controlled trial, women admitted to the hospital in threatened preterm labor (between 24 and 34 weeks' gestation) were randomized to receive atosiban or usual care (beta-agonists, calcium channel blockers, magnesium sulphate, or any other tocolytic, alone or in combination, and/or bed rest).
Results: In women randomized to receive atosiban (n=295) or usual care (n=290), significantly more women receiving atosiban remained undelivered at 48 h with no alternative tocolytic compared with usual care (77.6% vs. 56.6%; P<0.001). The proportion of women remaining undelivered after 48 h was comparable between the treatment groups. However, more women in the atosiban group required no additional tocolytics (85.1% vs. 62.8%; P<0.001). Maternal and fetal safety was significantly superior with atosiban. Neonatal safety was comparable.
Conclusions: These findings support the use of atosiban to delay preterm birth and are consistent with previously conducted, randomized, controlled trials. Atosiban was associated with fewer maternal and fetal adverse events compared with other tocolytics, and presented no safety concerns for either the mother or the unborn baby.