Is it normal to have your period twice in one month, once a year?

Depends...: Menstrual cycles are subject to stress, age, medication effects, pregnancy(obviously), and so on. Twice in one month is most likely stress related; once per year may be ok if you are perimenopausal...However if not then you should go visit with your primary care physician for an evaluation; of even your ob/gyn if that applies.

No, it's not: There are a number of issues that can lead to oligomenorrhea, which is the term for infrequent menstruation. It can be caused by a hormone imbalance, an anatomic issue with your uterus or your cervix, or excessive exercise, to name a few. Your physician should be able to determine the cause with an exam and a few tests.

Depends on question: If a woman has a menstrual period once a month, during 11 months of the year, but has 2 menstrual periods during one month each year, that is a normal pattern. It means her cycle length is 28 days (13 periods a year). However, if she has a period twice in one month, once a year with no periods during the other 11 months, that would be unusual, and she should be evaluated by her doctor(s).