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 Placenta in which vessels seperate before reaching margin is? and explain in detail?
Velamentous placenta REF: Dutta 6th ed p. 219 The branching vessels traverse a ceain distance in the membrane before they separate to supply it is seen in velamentous placenta Battledoor placenta: the cord is attached to the margin.