Objective: Evaluate the effectiveness of treatment preterm labor with Nifedipine in 28 - 34 gestational weeks. Methods: Prospective longitudinal study on 197 women with singleton pregnancies, gestational age of 28 - 34 weeks, the diagnosis of preterm labor from 01/10/2012 to 05/30/2013 in High risk - pregnancy department of Hung vuong hospital.