system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Norplant 1 is expected to be effective up to:
assistant
The correct answer is  Norplant 1 contains 6 silastic capsules of which each contains 36 microgram of levonorgestrel. It is expected to be effective for up to 5 years. Ref: Shaw's Textbook of Gynaecology, 12th Edition, Page 179.