N94: Pain and other conditions associated with female genital organs and menstrual cycle

N94.4: Primary dysmenorrhoea

This lining of the uterus thickens at the start of each normal menstrual cycle. It is then expelled when you have your period. This process is controlled by various sex hormones.

Pain associated with menstrual periods can occur in the lower abdomen. It may also radiate to the back or thigh.

You have been experiencing pain since your first menstrual period.