With regard to the use of tocolytic therapy for preterm labor, the ICSI Technology Assessment Committee finds the following:
The effectiveness of magnesium sulfate, nifedipine, and ritodrine may be comparable when used to delay delivery for 24 to 48 hours but with limited data from placebo-controlled trials it is impossible to conclude that any of the agents is superior to no treatment. If achievable, a delay would enable the administration of corticosteroids and/or permit the transfer of the patient to a tertiary care center. The side effect profiles do differ and should be considered when a tocolytic agent is to be used. (Conclusion Grade II)
Long-term therapy (after a successful acute administration) has not been found to be effective in preventing preterm birth, reducing the risk of recurrent preterm labor, or improving fetal outcome.
With appropriate selection and monitoring, tocolytic therapy is a relatively safe procedure. Although side effects are generally minor, they can be major and life threatening, including pulmonary edema, cardiac arrest, and death. Administration of pharmacologic tocolysis is a complicated procedure that should only be initiated in an inpatient care setting by those familiar with the implications and potential complications.