Endometriosis UK says one in 10 women of reproductive age in the UK suffer from endometriosis.
It adds that the prevalence of endometriosis in women with infertility can be as high as 30 to 50 percent.
The Royal College of Nurses says: “Women of any age can be affected by endometriosis but it is rare for the condition to manifest before a girl has her first period.
“Teenagers who suffer with painful periods, experience fainting or collapse when having a period, or who miss school because of their period problems should be considered as possibly suffering from the condition.”