Objective: Epidemiological studies on the cardiovascular risk of progestagen-only contraceptives are rare. With the present study we aimed to investigate the effect of the low-dose etonogestrel-releasing contraceptive implant Implanon® on cardiovascular risk factors, including markers of inflammation.
Design: Longitudinal study.
Setting: Family planning centre of a University Hospital.
Subjects: Thirty-six healthy, nonsmoking women with regular cycles (n = 18 controls without hormonal contraception; n = 18 cases requesting the insertion of Implanon®).
Measurements: Blood samples for the determination of C-reactive protein (CRP), nitric oxide (NO), sex hormones and plasma lipids were taken in the early follicular phase of the cycle in both groups. A second sample was taken 12 weeks after Implanon insertion or in the controls during the early follicular phase of cycle 4.
Results: Implanon treatment caused a 36% decrease in CRP (P < 0·06) and a significant decrease in high density lipoprotein (HDL) (P < 0·007), low density lipoprotein (LDL) (P < 0·001), cholesterol (P < 0·001), testosterone (P < 0·05) and SHBG (P < 0·002). Levels of NO, oestradiol and progesterone were not affected in either group. The cholesterol/HDL ratio did not change in Implanon carriers. There was a significant correlation between the cardiovascular risk factors CRP, cholesterol/HDL ratio and NO.
Conclusion: The progestagen-only implant Implanon does not exert a negative effect on the cardiovascular risk factors CRP, cholesterol/HDL ratio and NO. These results suggest that the use of a progestagen-only contraception does not increase cardiovascular risk factors in healthy young women.