Objective: Although immediate post-placental IUD insertion is considered safe and effective, later postpartum insertions have been discouraged. We conducted this study to assess acceptability and feasibility of conducting a clinical trial to investigate insertion of a levonorgestrel-releasing intrauterine system (LNG-IUS) 10 minutes to 48 hours after vaginal delivery. Methods: Prospective clinical study of women enrolled at 27-40 weeks gestation with an uncomplicated pregnancy. Women who met post-delivery criteria received the LNG-IUS under ultrasound guidance 10 minutes to 48 hours after vaginal delivery. Follow-up visits occurred 6, 12, and 24 weeks after LNG-IUS placement to assess participant satisfaction and LNG-IUS location. Statistical analysis included Student t-test, Mann-Whitney U test, and chi-square, for comparisons of means, medians and proportions. Results: Forty women were enrolled from July 2009 to January 2010. The median age was 23 years and median gravidity was 3. Median gestational age at enrollment was 35 weeks. Of the 29 women (73%) who received an LNG-IUS immediately after the delivery 19 women (67%) had the LNG-IUS in place when they exited from the study, and all 29 women said they would have the LNG-IUS placed in this setting again. Ten of the 29 (33%) women completed the study entirely.