O-33: Should long-term hormonal contraception be reconsidered? Metabolic and inflammatory outcomes in women using oral contraceptives and the levonorgestrel-releasing intrauterine device in a general population

Abstract

Despite prolonged use during reproductive life, the impact of many commonly-used contraceptive agents on the risk of subsequent metabolic and cardiovascular disease remains controversial. We compared the metabolic and cardiovascular effects of two widely-used contraceptive regimes: the levonorgestrel-releasing intrauterine device (LNG-IUD) and oral contraceptives (OCs). We investigated the effects of the use of these two contraceptive regimes in a representative sample of 2814 women from a general population based Northern Finland Birth Cohort born in 1966. A range of anthropometric, cardiovascular, metabolic and inflammatory phenotypes were measured at age 31 years. Women were classified as OC-users (N=687), LNG-IUD users (N=168) or using no hormonal contraception (reference group, N=1959). Compared to the reference group, OC-users had higher blood pressure (BP), systolic BP median 121 (interquartile range 114, 129) vs. 118 (111, 126) mmHg, and diastolic BP 76 (69, 82) vs. 74 (68, 82) mmHg, raised levels of inflammatory indices [C-reactive protein 1.90 (0.80-4.70) vs. 0.60 (0.30-1.40) mg/L], and impaired insulin sensitivity [lower homeostasis model assessment, HOMA%S 661 (547, 809) vs. 720 (578, 881)]. In contrast, LNG-IUD-users displayed no unfavorable changes in BP, lipid profile or insulin sensitivity, when compared to those on no hormonal contraception. OC-usage was associated with adverse changes in several metabolic, cardiovascular and inflammatory parameters, consistent with an increased future risk of cardiovascular and metabolic disease. No such changes were associated with LNG-IUD usage. These data suggest that non-oral hormonal contraception may offer long-term health benefits over oral methods.