After internal review board approval from the obstetrics and gynecology department of Kasr Alainy hospital, 130 patients will be recruited in a randomized case control study. The patients will be recruited from the emergency admissions department, after fulfilling the recruitment criteria. In an independent case-control study the Sample size was calculated using an odds ratio of exposure to CP of 0.14 (95% CI 0.05-0.51) (Grether et.al, 1998), where the alpha level error was fixed at 0.5 and the power was set at 80%, the optimal sample size was calculated to be 65 patients in each arm.