Delaying or even stopping menstruation can't be done manually, unless having "the implant" or "the shot", which are anti-pregnancy implants/shots. Menstruation is a natural part of life.
Could be pregnancy or it could be that you're starting menopause. It could also be thyroid hormone imbalance, or a number of other things. See your doctor for an accurate diagnosis.
The question is pretty vague. The answer to the question as asked is certainly "yes". That's not as helpful as it could be; you might want to go into more detail as to precisely what sort of...
Stress, environmental changes, moving to a new place, unhealthy eating habits, excessive exercise, pregnancy.....the list of possible reasons is a long one.
I dont want to mean to put pressure on you, but you should go see your doctor as if you dont take it seriously, some major health issues might occur, the best option is to see your doctor hope I was...