**10. Laboratory testing**

To exclude other causes of pelvic pain, laboratory investigations are often undertaken. Initially, a complete blood count (CBC), urinalysis and urine cultures, vaginal cultures, and cervical swabs may be obtained to exclude infections or sexually transmitted infections that may cause pelvic inflammatory disease (63).

Although concentrations of the cancer antigen CA125 are slightly raised in some women with endometriosis, the test neither excludes nor diagnoses endometriosis and is not considered useful in establishing the diagnosis. The threshold for surgery is unlikely to be influenced by the CA125 concentration and the guidelines from the Royal College of Obstetricians and Gynecologists described CA125 as having only limited value as either a screening or a diagnostic test (15).
