Primary aim: To study the outcome of intracytoplasmic sperm injection (ICSI) using long protocol. Analysis of the average number of days of stimulation, the incidence of ovarian hyperstimulation syndrome (OHSS), and the number and quality of oocyte retrieved. Secondary aim: Correlation of the outcome against the stimulation phase length Method: Retrospective study of 50 patients who underwent in vitro fertilisation (IVF) using the long protocol in our ART unit during December 2014 to December 2015. All clinical observations including the patient details, number of days of stimulation, the number of oocytes retrieved, the occurrence of OHSS were collected and tabulated. All clinical data were statistically analyzed. Result: The clinical outcome of ICSI using long protocol was satisfactory. In the study group, we achieved 72% grade 1 embryo (36) and 2 weeks after embryo transfer the biochemical testing for pregnancy showed positive pregnancy in 52% (26). The average stimulation phase length was 13.5 days, (SD 5.5). The incidence of severe OHSS needing hospitalization and treatment was 2% (1/50). 8 patients observed to have evidence of mild OHSS. OHSS was observed in patients with a shorter period of stimulation phase, mean SPL among OHSS patient was 11.38 ( SD -1.6). However, it was not statistically significant ( p–0.507). The stimulation phase length did not correlate with the quality of oocyte nor the pregnancy rate as hypothesized theoretically. Conclusion: The present study shows satisfactory clinical outcome using long protocol,the stimulation phase length did not show significant ill effects in the clinical outcome (72% grade 1 embryo, 52% pregnancy), nor increase complications like severe OHSS.