Amenorrhea is the absence of menstruation or missed menstrual periods for more than three months. 

According to WebMD, a health website, there are two types of amenorrhea: primary amenorrhea and secondary amenorrhea.  

Primary amenorrhea is when a young woman has not had her first period by the age of 16. Secondary amenorrhea is when a woman who has had normal menstrual cycles stops getting her monthly period for three or more months.

Amenorrhea can be caused by any number of changes in the organs, glands, and hormones involved in menstruation.

Dr Tekle G. Egiziabher, an obstetrician and gynecologist at the Rwanda Military Hospital, says that even if one isn’t pregnant and they miss their periods for a period of at least four consecutive months and above, then that is when they should worry.

He says that missing periods for at least two or three months may not necessary mean that one is suffering from Amenorrhea as there are many other factors that could lead to this.

"Menstrual periods come with hormonal variations sometimes stimulated by what one eats or even change of environment. If one has changed their diet or the environment they have been staying in then it can easily affect their menstrual cycle,” he said.

He further notes that depression and stress can also lead to missing periods and in the long run amenorrhea.

Dr Taekle states that sometimes amenorrhea is caused by side effects of particular medications such as some contraceptives. He further notes that in situations where one is breastfeeding, using birth control pills, pregnant or hitting menopause then its normal to miss one’s menstrual periods.

Some of the signs of Amenorrhea besides missing one’s periods in a row for many months include constant headaches, milky nipple discharge, hair loss and changes in one’s vision.