Twenty-four month comparison of Apolipoproteins A-1, A-II, and B in contraceptive implant users (Norplant® and Implanon®) in Birmingham, United Kingdom

Abstract A 2-year prospective, randomized study of 60 implant users was performed to evaluate fasting serial serum apolipoprotein A-I, A-II, and B levels before insertion and every 3 months in users of two contraceptive implants releasing levonorgestrel (Norplant®) and 3-ketodesogestrel/etonogestrel (Implanon®) in Birmingham, United Kingdom. All changes in serum apolipoprotein concentrations, irrespective of an increase or decrease, were smaller than one standard deviation of the mean concentration at baseline and did not exceed the normal range for the laboratory, thus implying no evidence of an increased risk of coronary heart disease.