Effect of Implanon((R)) use on selected parameters of thyroid and adrenal function

In this article, the effects of Implanon(R) implant use on thyroid and adre nal function was compared with those of Norplant(R) implants. In this 2-yea r open randomized study of 80 implant accepters, we found that both implant s may induce minimal changes in thyroid hormones and cortisol levels, possi bly secondary to alterations in the respective binding globulins in the ser um. These alterations in thyroid and adrenal function would have no clinica l significance in healthy women. In the Norplant group, sex hormone-binding globulin levels decreased, whereas increased levels were found in the Impl anon users at the end of 2 years. These findings lend support to the fact t hat etonogestrel, released from Implanon implants, is significantly less an drogenic than levonorgestrel, released from the Norplant implants. (C) 2001 Elsevier Science Inc. All rights reserved.