Ovarian cysts: presence and persistence with use of a 13.5mg levonorgestrel-releasing intrauterine system.

Transvaginal ultrasound follow-up of women during a 3-year clinical trial of LNG-IUS 13.5mg showed that ovarian cysts were present in 1.6% of participants at screening and 1.1-2.4% at each subsequent visit. Eighty-eight percent were ≤5cm, with none >8cm. No ovarian cysts persisted beyond Month 9, suggesting a functional etiology.