Collywobbles but does not come menstruation how to return a responsibility

If a woman has already reached her menstrual period and has shown a series of menstrual precursors such as obvious abdominal pain, but has not shown obvious vaginal bleeding, this is likely due to environmental influences such as cold, strenuous exercise, mood swings, etc. Menstruation delay is caused. Women's menstrual cycle is 28-30 days, and it is normal to advance or delay within 1 week. If a woman of childbearing age with a regular menstrual cycle has sex, the first thing you need to do is to rule out the possibility of pregnancy, and you need to pass a pregnancy test paper or pass a blood test. If early pregnancy is ruled out, it is affected by the external environment caused by menstrual changes, in the absence of continuous performance of menstrual delay, occasionally show a menstrual delay, you can wait appropriately, if continuous performance of menstrual delay, it belongs to irregular menstruation, need further examination and diagnosis.