RESUMO
BACKGROUND:Subdermal contraceptive implants as a novel contraceptive method have been extensively used worldwide.OBJECTIVE:To review the research progress in the non-biodegradable and biodegradable long-term subdermal contraceptive implants and to explore their advantages and disadvantages.METHODS:A computer-based search of CNKI,Wanfang,and PubMed (1967-2015) was performed by the first author for relevant articles,using the key words of contraceptive implants,non-biodegradable,biodegradable in Chinese and English,respectively.Initially 240 articles were retrieved,and finally 70 articles were included in result analysis.RESULTS AND CONCLUSION:Long-term subdermal contraceptive implants that pass through the local capillaries into the blood circulation system can avoid the gastrointestinal absorption,improve the bioavailability of drugs,and reduce adverse drug reactions.According to the performance,there are two kinds of drug carriers,non-biodegradable and biodegradable.Although non-biodegradable implants have been widely used and the contraceptive effect is excellent,the implants must be removed surgically because they cannot be absorbed or metabolized in the body.Significant efforts have been devoted to developing biodegradable implants because they can degrade at the end of use.However,the utility of some biodegradable polymers as drug carriers in implantable applications has been hampered by their shortcomings,and further study on alternative materials is urgently required.