Why does menstruation occur during breastfeeding but stop after weaning?

After menstruation resumes during breastfeeding, the cessation of menstrual periods following weaning may be caused by various factors. Hormone levels in women undergo changes during lactation, which can affect the menstrual cycle. After weaning, as hormone levels such as prolactin gradually return to normal, menstrual regularity may be temporarily disrupted. Other factors such as life stress, emotional fluctuations, and dietary habits may also influence menstruation. If menstruation does not resume for an extended period, it is advisable to consult a doctor and undergo necessary examinations to rule out pregnancy or other potential health issues. The doctor will provide appropriate diagnosis and treatment recommendations based on the individual's specific situation.