title: Long-term contraception by a single silastic implant-D containing norethindrone acetate in women: a clinical evaluation.
mesh_terms: D003274:Contraceptive Devices, Female; D004343:Drug Implants; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D009640:Norethindrone / Q000494:pharmacology*; D012826:Silicone Elastomers; D013997:Time Factors
chemical_list: D004343:Drug Implants; D012826:Silicone Elastomers; D009640:Norethindrone