Objective To describe clinical intrauterine insemination (IUI) outcomes among infertile patients with different infertility indications, and further compare reproductive outcomes between natural cycle (NC) and ovarian stimulation cycle (OSC) IUI.Materials and methods A total of 1451 infertile couples that underwent their first IUI cycle with husband sperm were included in this retrospective cohort study. The clinical pregnancy rates and live birth rates were compared between NC and OSC by diverse infertility indications.Results A total of 833 NC-IUI and 618 OSC-IUI cycles were available for analysis. Logistic regression showed patients with ovulatory disorder had significantly higher clinical pregnancy (21.99% vs 14.15%; AOR 1.992, 95% CI 1.207–3.288) and live birth rates (18.67% vs 11.51%; AOR 2.326, 95% CI 1.312–4.124), along with a higher preterm birth rate (p = 0.032) when compared to the normal ovulation group. Among normal ovulatory patients, NC-IUI achieved higher clinical pregnancy rate than OSC-IUI in endometriosis (12.70% vs 8.00%), tubal infertility (16.67% vs 7.14%), and male factor group (15.92% vs 9.40%, p = 0.047), with similar live birth trends. For unexplained infertility, OSC‑IUI presented higher clinical pregnancy (20.51% vs 12.89%, p = 0.205) and live birth rates (12.82% vs 11.11%, p = 0.970), without statistical significance.Conclusion Ovulatory disorder was independently associated with favorable IUI outcomes. For patients with endometriosis, tubal factor infertility and male factor infertility, NC-IUI showed a potential trend of clinical applicability, while OSC-IUI tended to be more suitable for unexplained infertility; however, these subgroup differences did not reach statistical significance and warrant further validation in larger cohorts.
Jia et al. (2026) studied this question.