Irregular period? I started my period when I was 11, and it was normal. At 15 it started coming every 2 -3 months and as I get older its farther apart. I'm 18 now and I have a period anywhere from every 4-6 months and sometimes even longer in between. At t

Irregular . Irregular menstrual periods can be due to many things, with pregnancy being the first on the list of someone who is 18 years old. If pregnancy is ruled out, the not ovulating would be most likely the second common reason. Working with your gynecologist would be advised, with treatment often consisting of birth control pills to prevent pregnancy and keep the cycle regular. Dr. Jane frederick www.Havingbabies.Com.