['We performed a pilot evaluation of a new formulation of levonorgestrel butanoate (LB) designed to be a long-acting injectable (6 months) contraceptive to determine pharmacodynamic end points in normal-body mass index (BMI) and obese women.', 'Obese (BMI ≥30 kg/m', 'A total of 14 women enrolled and completed the study [normal BMI n=9, median BMI 22.7kg/m'] Does levonorgestrel butanoate intramuscular injection reliably suppress ovulation for 90 days in obese and normal-BMI women : a pilot study?