Endometriosis – It is defined as the presence of functioning endometrial tissue (both glands and stroma) outside the uterus i.e. sites other than uterine mucosa. 

Sites of endometriosis: 

  • Ovary 
  • POD 
  • Uterosacral region
  • Rectovaginal septum 
  • Sigmoid colon
  • Abdominal scar following hysterectomy
  • Remote sites- Pleura, lungs, deep tissues of arms and thighs

Types of endometriosis:

Ovarian endometriosis- 

  • Can be either superficial or deep
  • The small superficial dark bluish cysts contain altered blood; from these the escape of small quantities may lead to the formation of adhesions to the surrounding tissues and structures. When these adhesions broke down the cysts are damaged and the material escapes.  
  • These are likely endometrial deposit becomes invaginated into the ovarian surface or it may be an inflammatory response to the ovarian surface leads to adhesion formation.

Bowel endometriosis: 

  • In this the rectum is involved, most commonly at the retrovaginal septum, the lesions are visible on the peritoneal surface and in the peritoneal surface and in the muscular layers, mucosa involvement is rare. 
  • Patient generally presents with abdominal pain and pelvic discomfort. 
  • There can be partial or complete obstruction. The obstruction is due to fibrosis affecting that wall of bowel, most commonly found in the ileac region and the sigmorectal junction. 

Lower genital tract endometriosis:

Cervix and vagina appears bluish in color and usually cystic. On palpitations there is tenderness, usually during menstruation. The referable symptoms are – dysmenorrhea, dyspareunia, and perhaps bleeding. 

Urinary tract endometriosis 

  • This may be seen on cystoscopy. 
  • This may occur with associated symptoms of frequency, hematuria, abdominal pain, and dysuria. 

Umbilical endometriosis 

  • Usually seen as cyclical umbilical pain with a bluish discoloration at the time of menstruation. This can be treated by excision.

Endometriosis in scars: 

  • Inflammation in a laparotomy or cesarean section scar is tender and painful, especially during menstruation. 

Pelvic endometriosis

There is typically presence of small black dots so called powder burns seen on the uterosacral ligaments and pouch of Douglas. Fibrosis and scarring in the peritoneum surrounding the implants is also a typical finding. Other subtle appears- red flamed shaped areas, red polypoid areas, yellow brown patches, white peritoneal areas, circular peritoneal defects.

Peritoneal endometriosis

This is the red endometriosis which is characterized by numerous proliferative glands with a columnar or pseudo-stratified epithelium and glandular component of these lesions has very alike appearances.

Rectovaginal endometriosis

This type of endometriosis occurs between the rectum and vagina, and has a different histological appearance.

These rectovaginal nodules may arise separately between and through a different process and to the peritoneal endometriosis.


  1. Sampson’s theory – Retrograde menstruation 

– Endometrial fragments are travel to peritoneal cavity through tubes. 

– Viable cells are implants and grow. 

– Young females with obstructive abnormalities of genital tract often develop endometriosis. 

  1. Coelomic metaplasia theory:

– Chronic irritation of the peritoneum by menstrual blood may leads to coelomic metaplasia which results in endometriosis. 

– The mullerian tissue remnants may be trapped within the peritoneum, alternatively. 

– Undergoing metaplasia transformed into endometrium. 

  1. Lymphatic and vascular metastases theory: 

–  The lymphatic and hematogenous spread of endometrial cells. 

– Extensive transmission of lymphatics between uterus, tubes, ovaries, pelvic and vaginal lymph nodes, kidneys & umbilicus. 

  1. Direct implantation

– According to this theory, the endometrial or decidual tissues start to grow in susceptible individual, when implanted in new sites.  These sites are abdominal scar following hysterectomy, cesarean section, tubectomy and myomectomy. This theory also explained endometriosis at the episiotomy scar, vaginal or cervical site.  

  1. Genetic factors:  The risk of developing endometriosis is 7 times more if first degree relative has it.
  2. Immunological factors: Decreased clearance of endometrial cells due to reduced natural killer cell activity or reduced morphologically activity. 
  3. Inflammation- Endometriosis can be associated with subclinical peritoneal inflammation. 


  • The endometrium in the ectopic sites potentially undergo changes under the action of ovarian hormones. 
  • Shedding and cyclic growth continue till menopause. The periodically shed may remain encysted, the cyst ruptures. 
  • As the blood is an irritant, there is dense reaction of the tissue surrounding the lesion with fibroids. If it occurs on the pelvic peritoneum, it produced adhesion and puckering of the peritoneum.
  • If encysted, the cyst become enlarged with cyclic bleeding. The serum gets absorbed between the periods and the content inside become chocolate colored. Hence the cyst is called chocolate cyst or hemorrhagic cyst, which is commonly located in the ovary.

Clinical presentation


– Dysmenorrhea, dyspareunia, and deep-seated pelvic pain.

– Commence before onset of menses and will continue throughout the menstrual cycle.

– Deep dyspareunia

Abdominal bleeding

  • may include premenstrual spotting, menometrorrhagia, polymenorrhagia.


  • majority of women with endometriosis have infertility.
  • Ovarian problems – anovulation, luteinized unruptured follicle, maturation defects, oocyte.
  • Tubal problem
  • Peritoneal factors
  • Sperm problems
  • Endometrium- implantation defects luteal phase defects.

Other symptoms

  • Clinical rectal bleeding or hematuria- extra pelvic endometriosis
  • Cyclic pain or bleeding at scar- scar endometriosis
  • Umbilical mass with cyclic pain- umbilical endometriosis
  • Cyclical hemoptysis and hemothorax- pulmonary endometriosis


  • Transvaginal ultrasound
  • CA-125
  • Laparoscopy
  • CT and MRI
  • Color doppler flow
  • Cystoscopy
  • Sigmoidoscopy
  • Anti-endometrial antibodies


  • Drug treatment
  • Drug therapy
  • Minimal invasive surgery
  • Surgery