You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Eligible couple is: and explain in detail?
Eligible couples (ECs): A currently married couple with wife in reproductive age group (15-45 years age) ECs are in need of family planning services There will be atleast 150 - 180 ECs per 1000 population in India EC register is maintained as Sub-centre.