The term amenorrhea refers to the non-occurrence or absence of menstrual flow for a period of time of at least six consecutive months.
In cases of “thinning” menstruation, for example, due to particularly long menstrual cycles (5-7 weeks instead of four) or irregular ovulations (one or a few missed cycles), this is more properly called oligomenorrhea.
Amenorrhea can have innumerable causes and is usually associated with transient or persistent impairment of female fertility.
