The dear doctor! Respond! Whether is normal that from first day predydushch...

[Anja 16 years]

The dear doctor! Respond! Whether what from first day previous monthly till first day of these or it has passed or has taken place 25 days is normal? And already almost 4 months as monthly every month begin earlier for 4 5 days? Respond please!

[Irtuganov N.S.]

Dear Anja! Into a range of "normal" duration of a menstrual cycle of 25 days enters, but if there is a constant change of duration - expediently to visit or attend the doctor