Economic Analysis of Long Term Reversible Contraceptives

Objective: To examine the economic impact of a new implantable contraceptive, Implanon®, in comparison with other available contraceptive methods.

Design: This was a modelling study using cost data derived from national published sources and effectiveness data from either controlled clinical trials (Implanon®) or reports in the literature (other contraceptives). In the baseline analysis, Implanon® was compared with 2 long term reversible contraceptives, Norplant® and Mirena®. Further analyses were then carried out comparing Implanon ® with Depo-Provera® and with combined oral contraceptives.

Setting: The study concentrated on the UK, but also made reference to several other European countries.

Main outcome measures and results: The baseline analysis showed that all 3 long term reversible contraceptives produce very good rates of return, with Implanon® providing the best rate of return (both average and internal) of the 3 methods. The payback period for Implanon® was calculated as 146 days, compared with 339 and 368 days for Norplant® and Mirena®, respectively. In terms of cost effectiveness, the cost per protected year for Implanon® was £95, compared with £146 and £168 for Norplant® and Mirena®, respectively. In comparison with Depo-Provera® (an injectable contraceptive), Implanon® was both less costly and more effective, the cost per protected year for Depo-Provera® being £131. The threshold beyond which Implanon® delivers cost savings compared with combined oral contraceptives was at a failure rate of 4.9% for the combined pill.

Conclusions: Reversible long term approaches to contraception provide an effective and efficient use of healthcare resources and generate an excellent return on public investment. Implanon® produces better rates of return than both Norplant® and Mirena®, and is also more cost effective in terms of cost per pregnancy avoided and cost per protected year than Norplant®, Mirena®, DepoProvera® and oral contraceptives.