Atosiban Protocol for Women with Preterm Labor
Atosiban is an effective tocolytic agent for delaying delivery in women with preterm labor, with a better maternal safety profile than beta-agonists and should be administered according to a three-step protocol: initial bolus followed by high-dose infusion, then maintenance infusion. 1, 2
Indications for Atosiban
- Atosiban is indicated for women between 24-34 weeks gestation with preterm labor to delay delivery for 48-72 hours, allowing time for administration of antenatal corticosteroids and maternal transfer to a tertiary care facility 3
- The primary goal of tocolytic therapy is not to prevent preterm birth entirely but to gain time for interventions that improve neonatal outcomes 3
- Atosiban has demonstrated effectiveness in delaying delivery in women as early as 18-24 weeks gestation 4
Administration Protocol
Initial Treatment (Acute Tocolysis)
- Step 1: Administer intravenous bolus dose of 6.75 mg 1, 5
- Step 2: Follow with high-dose intravenous infusion of 300 μg/min for 3 hours 1, 5
- Step 3: Continue with maintenance intravenous infusion of 100 μg/min for up to 48 hours 1, 5
Maintenance Therapy (If Needed)
- After successful acute tocolysis, maintenance therapy can be considered 6
- Administer as continuous subcutaneous infusion via pump at 30 μg/min 6
- Continue maintenance therapy until 36 weeks' gestation 6
Efficacy and Monitoring
- Tocolytic effect typically begins within 3-10 minutes (median: 6.5 minutes) 4
- Complete cessation of contractions usually occurs within 3-12 hours (median: 7.5 hours) 4
- Monitor for:
Safety Profile and Advantages
- Atosiban has a more favorable maternal safety profile compared to beta-agonists like salbutamol and ritodrine 1, 5
- Significantly fewer maternal cardiovascular side effects compared to beta-agonists (4.0% vs 84.3%) 5
- Lower rate of treatment discontinuation due to adverse events compared to other tocolytics 2, 5
- Neonatal outcomes are comparable to other tocolytic agents 1, 5
Important Considerations
- Atosiban is as effective as beta-agonists in delaying preterm birth for at least 48 hours 1, 5
- Consider concurrent administration of antenatal corticosteroids for fetal lung maturity when gestational age is ≤34 weeks 3
- For deliveries before 36 weeks gestation, antenatal corticosteroids are recommended to reduce the risk of respiratory distress syndrome 7
- In cases of preterm labor before 32 weeks, consider magnesium sulfate for fetal neuroprotection 8
Contraindications and Cautions
- Atosiban should not be used when continuation of pregnancy is contraindicated 1
- Use with caution in multiple gestations 5
- Monitor for injection site reactions during maintenance therapy 6
Clinical Pitfalls to Avoid
- Remember that no tocolytic has been consistently shown to improve neonatal outcomes or reduce the overall rate of preterm birth - the main benefit is gaining time for corticosteroid administration and maternal transfer 3
- Do not continue tocolysis when delivery would be beneficial for maternal or fetal indications 3
- Avoid using atosiban as a long-term solution for preventing preterm birth without addressing underlying causes 3