-IUD is the best option. It is reliable and doesn’t interact with many immunosuppressive therapies.
Female fertility typically increases post-transplant so patients need contraception. “Pregnancy should be avoided during the 12 months following transplantation because of the increased risk of preterm delivery and graft rejection.”
Further Reading / Reference
US medical eligibility criteria for contraceptive use, 2016. MMWR Recommend Rep 2016;65(3):1-103.
Primary care of the solid organ transplant recipient. Am Fam Physician 2016;93(3):203-210.