Related Experiment Video
Updated: Aug 30, 2026

Differential Effects of Lipid-lowering Drugs in Modulating Morphology of Cholesterol Particles
Published on: November 10, 2017
Effect of Implanon and Norplant subdermal contraceptive implants on serum lipids--a randomized comparative study
Arijit Biswas1, Osborne A C Viegas, Asim C Roy
1Department of Obstetrics and Gynaecology, National University Hospital, National University of Singapore, 5 Lower Kent Ridge Road, Singapore, Singapore. obgab@nus.edu.sg
Abstract:
The objective of this study was to assess the possible differences in effects of Implanon (etonogestrel 68 mg, single-rod) and Norplant (levonorgestrel 36 mg, six capsules) implants on serum lipids over 2 years of use. In this 2-year open randomized study of 80 implant acceptors, selected serum lipids were tested before implant insertion and at 6, 12 and 24 months after implant insertion. The lipid parameters evaluated were: total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides, apolipoprotein A-I and apolipoprotein B. During the 2 years, the serum lipid pattern in the Implanon users was not significantly different from that of the Norplant users. There was slight decrease in HDL-C levels in both the groups but there were no significant changes in the HDL/TC ratio and the HDL/LDL ratio. Although it was statistically significant, the magnitude of decrease in HDL-C from preinsertion levels in Implanon users was only 5.8% at the end of 2 years.

