 - Included patients will receive tocolysis according to Ain Shams University Maternity hospital protocol which is recommending usage of calcium channel blocker Nifedipine Initially 10mg orally every 15 minutes, up to 4 doses of Nifedipine to stop contractions. After this slow release nifedipine. It has been found that an 8 hourly dosage of 40mg - 20mg - 40mg calcium channel blocker is suitable for most women. This is in addition to use of steroids to enhance lung maturity dexamethasone, 6 mg intramuscular 12 hrs for 48 hrs 