Glucose metabolism among Norplant users in northern Nigeria

Safety of implantable contraceptives for women: data from observational studies

Contraceptive implants are registered in over 60 countries and have been used by millions of women for three decades. This article reviews findings from observational studies on the safety of contraceptive implants and examines the risk of specific health outcomes. Fifty-five articles were reviewed, and the body of evidence for each health outcome was summarized. Available evidence suggests that contraceptive implants are safe and, overall, implant users do not experience adverse events at rates higher than women not using implants. With respect to specific outcomes, the evidence suggests no increased risks of pelvic inflammatory disease, decreased bone mineral density, anemia, thrombocytopenia, or death with implant use. The evidence was too limited to draw meaningful conclusions for neoplastic disease, cardiovascular events, and HIV/AIDS. Nonsignificantly elevated associations were reported for diabetes, serious mental disorders, and rheumatoid arthritis. Conditions for which risks were marginally, yet significantly, elevated were hypertension and gall bladder disease.

Metabolic effects of implantable steroid contraceptives for women

The metabolic impact of progestin-only contraceptives is less than that of combined oral contraceptives. Subdermal contraceptive implant systems that provide a sustained release of low levels of progestins are now becoming widely available. This review evaluates the metabolic effects of currently available products that release the progestins levonorgestrel (Norplant, Jadelle, and their Chinese equivalents); etonogestrel (Implanon); nomegestrol acetate (Uniplant); and Nestorone, formally called ST-1435 (Nestorone implant/Elcometrine). Data on liver, kidney, and renal function; carbohydrates and insulin release; hemostasis; blood pressure; and lipids are considered. The metabolic effects reported for these methods as a whole were minimal. Any changes were generally within the normal range for the populations studied and, therefore, are unlikely to be of clinical significance. However, all published studies have been conducted in healthy populations of women. To inform clinical practice, the field would be well served to have additional empiric data from well-designed, well-implemented, and well-reported trials in women who are deemed to be at elevated risk for certain diseases including cardiovascular disease and diabetes.