 Newer developments, however, point to the improved effectiveness of anti-prostaglandin agents and calcium channel antagonists as it concerns treating such patients7,11. Calcium channel antagonists are just as effective and appear to be safer than magnesium for primary tocolytic treatment of women in preterm labor12-14. Tocolytic treatment with anti-prostaglandin drugs such as indomethacin, a Cox-1 inhibitor, has demonstrated them to be the most effective and most rapid tocolytic agent available15. Initially there were reports of increasing complications with the use of this drug16,17. However, it has been shown that these concerns are unwarranted if indomethacin use is limited to 48 hours per treatment cycle and the amniotic fluid assessed for oligohydramnios; therefore, in pregnancies 32 weeks there ample evidence to justify its use as a primary tocolytic18,19,20. This is particularly true with the newer agents of this class Cox-2 inhibitors which have fewer fetal side effects7,11. In sum, however, there are no randomized trials which demonstrate the effectiveness of these three types of agents. 