Does taking contraceptives before menstruation delay menstruation?

Taking contraceptives before menstruation may delay menstruation.

The hormonal components contained in contraceptives, such as progesterone, can affect a woman's endocrine system. Changes in these hormones may interfere with normal menstrual cycles, resulting in delayed menstruation. The effects of taking contraceptives at different times before menstruation may also vary. If they are taken close to menstruation, they may be more likely to cause delayed menstruation; if they are taken a little further away from menstruation, their effects may be relatively complicated.

If menstruation is delayed for a long time or accompanied by other abnormal symptoms, such as abdominal pain and abnormal bleeding, they should be promptly examined and diagnosed to determine the cause and take appropriate treatment measures.