Oligomenorrhoea is used to define a period more than 35 days between two menstruation.

It is considered to be normal for the period between 2 menstruations to be between 21 to 35 days.However, if this time is over 35 days, this condition is called oligomenorrhoea and is the condition of rare menstruation.

It can be encountered in private matters of women and manifests as lack of menstruation or irregularity of menstruation.This condition is common in puberty as well as during pregnancy, menopause and breast feeding (lactation).If menstrual irregularity is in question, it should be checked to see whether one of these conditions apply, including pregnancy.If the reason for late menstruation is not caused by one of these conditions, it is needed to visit a doctor and identifying the cause of the problem.

For late menstruation, reasons such as anovulation (especially PKO), insufficient ovary capacity, Asherman syndrome are suspected.Medicine and protection methods might also be a cause.
The treatment is dependant on the diagnosis.