Yes it can be.

There are many causes of irregular menses. And the last thing that should come to your mind is actually infertility. However, some causes of infertility presents with irregular menses. So it is better to be examined by a Gynecologist, if it affects tour life. Good Lucks

It might be. It can arise from many things so it is better to consult a physician about it where he will do different hormone tests and prescribe you a medicine.

No, but this may make it harder for you to get pregnant.

Yhe miyagatem beteley mayet kjemeresh ymejemriyawechu 2 ametat lay

It accounts for 30-40% of all cases of Infertility

Normal menstrual cycle ranges from 21-35 day. ofcourse in the first 5 years it may even come every 3 or 4 month. And it is normal but there is a case called secondary amenorrrhea (when mense disappear for 6 months straight and this need's evaluation

Not at all