Tabriz Valiasr International Hospital Publication International Journal of Drug Research in Clinics 2980-9835 4 1 2026 01 01 Effect of Early Enoxaparin Treatment on Fertility Outcomes in Assisted Reproductive Technology: A Randomized Clinical Trial e1 e1 10.34172/ijdrc.2026.e1 EN Samaneh Sadat Hosseini https://orcid.org/0000-0002-6129-8467 Ramesh Baradaran Bagheri https://orcid.org/0000-0002-9853-6799 Sahar Morsali Journal Article 10.34172/ijdrc.2026.e1 2025 11 15 2025 12 20 Background: This study aimed to evaluate whether early administration of enoxaparin could improve the success of assisted reproductive technology (ART), particularly by enhancing endometrial receptivity and embryo implantation. Enoxaparin, an anticoagulant, has been proposed to modulate uterine blood flow and inflammatory pathways, potentially leading to better ART outcomes. Methods: In this randomized single-blind clinical trial, 90 infertile women undergoing IVF/ICSI were recruited and randomly assigned to two groups: an intervention group (n=45) receiving subcutaneous enoxaparin (1 mg/kg/day) starting three days before ART and continued until 14 days after embryo transfer, and a control group (n=45) receiving standard ART care. All analyses were conducted according to the intention-to-treat principle. Results: The overall clinical pregnancy rate across all participants was 13.3%. In the intervention group, 15.6% achieved clinical pregnancy compared to 11.1% in the control group (RR: 1.40, 95% CI: 0.49–4.00; P=0.535), indicating no statistically significant difference. Biochemical pregnancy occurred in 33.3% of women receiving enoxaparin versus 20.0% in the control group (RR: 1.67, 95% CI: 0.82–3.39; P=0.153), which also did not reach statistical significance. Rates of miscarriage and ongoing pregnancy were similar between groups. Due to the short follow-up period, no live birth outcomes were recorded. Conclusion: Early enoxaparin administration did not significantly improve ART success rates in this population. Based on these findings, routine use of enoxaparin as a primary or prophylactic adjunct in ART cycles is not supported.