Effect of subdermal levonorgestrel contraceptive implants, Norplant, on serum lipids.

Forty-seven normal non-smoking parous women were enrolled in a longitudinal study of the effect of use of the subdermal levonorgestrel implants, NORPLANT, on serum lipids. Blood samples were collected after an overnight fast before insertion and after three, six, nine and twelve months of use. The high-density lipoprotein cholesterol showed no change until the twelfth month when it was increased (P less than .05). Total cholesterol, low-density lipoprotein cholesterol and triglyceride levels decreased significantly during NORPLANT use.