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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.
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After childbih, the external cervical os is:
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The correct answer is  Before childbih, the external cervical os is a small, regular, oval opening. After childbih, the orifice is conveed into a transverse slit that is divided such that there are the so-called anterior and posterior lips of the cervix.