Objectives: To assess the outcome of treatment with only gonadotropin releasing hormone agonists (Gn-RHa) versus combined conservative surgery and Gn-RHa therapy in the management of sub-fertile patients with symptomatic uterine adenomyosis. Methods: A retrospective study of the two treatment modalities allocated to 40 sub-fertile patients with pathology-proven adenomyosis over a period of eight years was undertaken at the Obstetrics and Gynecology department, King Fahad Hospital, Dammam University, Saudi Arabia. Twenty-two patients (Group A) were treated with Gn-RHa alone, and 18 patients (Group B) received combined conservative surgery with Gn-RHa therapy. After completion of six courses of Gn-RHa injections, there was a 3-year follow up period for all patients. Treatment outcome included relief of symptoms, pregnancy rate and successful deliveries, which were compared between the two groups. Results: The patients in group A were younger in age, had lower CA-125 levels and shorter infertile years than Group B. Three (13.6%) spontaneous pregnancies resulted upto 18 months of stopping Gn-RHa in group A, while 8 (44.4%) pregnancies resulted upto 36 months in group B patients, which was statistically significant (p=0.0393). Term delivery occurred normally in one (4.5%) Group A patient, while 6 (33.3%) patients in Group B had cesarean section at term (p=0.0328). Conclusion: Combined conservative surgery and Gn-RHa may provide effective symptom relief, better reproductive performance in subfertile patients with uterine adenomyosis and longer period of pregnancy prospects after treatment than patients who recieved Gn-RHa alone. Due to the nature of this study, a well conducted randomized trial is needed in the future to assess the benefits of the two treatment modalities.