Background: Infertility affects approximately one in seven couples worldwide. IUI is a commonly used assisted reproductive technique, with success influenced by maternal age, ovarian response, infertility duration, and sperm quality. As evidence on age-related IUI outcomes in Bangladesh is limited, this study assessed IUI success according to maternal age among patients attending an infertility center in Rangpur. Methods: A retrospective observational study was conducted at LAB a One Infertility and IUI Center, Rangpur, Bangladesh, from July 2025 to June 2026. A total of 48 women aged 21–40 years undergoing IUI were included. Ovarian stimulation was performed using letrozole, clomifene, or FSH/HMG, followed by hCG triggering. Post-wash sperm count and motility were recorded. Maternal age was categorized as <30 and ≥30 years, and pregnancy following IUI was the primary outcome. Data were analyzed using IBM SPSS Statistics version 27 and presented as frequencies and percentages; p<0.05 was considered statistically significant. Results: Among 48 patients, 62.5% were <30 years, with 25–29 years being the most common age group (47.9%). Letrozole-based stimulation was most frequently used (52.1%), followed by clomifene (27.1%) and FSH/HMG (20.8%); all patients received hCG triggering. The overall pregnancy rate was 20.8%, with a higher rate among women <30 years than those ≥30 years (26.7% vs. 11.1%). Of the 10 pregnancies, 80.0% occurred in women <30 years. Overall, younger women showed more favorable observed IUI pregnancy outcomes. Conclusion: IUI demonstrated a 20.8% overall pregnancy rate, with more favorable outcomes observed among women younger than 30 years. Maternal age may be an important consideration when counseling couples regarding expected IUI success.