Rationale of performing the study As both medications i.e. CC and letrozole have been shown to be effective in inducing ovulation in PCOS patients, this study was performed in order to evaluate which regime (whether CC or letrozole) is the best to be used as the first line treatment for PCOS patients with infertility for local population. The best regime will therefore could be included in the protocol of management of infertility patients with PCOS so that the quality of patients' care could be improved.