How does endometriosis affect your patient’s fertility?

It is estimated that the percentage of women of reproductive age with endometriosis is 10-15%.

However, in a population of women dealing with infertility, this proportion jumps to between 25% and 40%. We, therefore, believe that part of a responsible work-up of patients presenting with infertility is an assessment of the possibility of her having endometriosis. Common symptoms such as dysmenorrhoea and dyspareunia are indicative of a potential problem but their absence does not rule out the diagnosis.

There remains considerable controversy regarding exactly how endometriosis affects fertility, as well as issues surrounding its natural history, pathogenesis, diagnosis, surgical treatment and fertility treatment options. In essence, endometriosis is often an inflammatory and scar-forming condition causing suffering among patients. Here, we look at a few ways in which endometriosis can affect your patient’s reproductive potential.


There are four variants of endometriosis related to infertility. They involve the formation of endometrioma, superficial peritoneal deposits, deeply infiltrating endometriosis (DIE), and adenomyosis. These four variants have similar pathogenesis, but have varied presentations and need different clinical management.

Ovarian endometrioma occurs in 17-44% of patients with endometriosis. There are four different ways in which ovarian endometrioma may affect fertility:

  • In about 15-25% cases the mechanism involves anovulation.
  • Fibrosis leads to the destruction of germinal epithelium resulting in abnormal rates of follicular development, premature follicular rupture and asynchrony in the oocyte maturation.
  • Histological data confirms inflammation and fibrosis of the surrounding ovarian cortex.
  • There is also increased tissue oxidative stress-inducing oocyte apoptosis and necrosis.
  • Over-aggressive ovarian surgery can also reduce the ovarian reserve and compound the problem.

The other forms of pelvic endometriosis have similarities in how they affect a woman’s fertility. These include:

  • Increased secretion of pro-inflammatory cytokines leading to impaired cell-mediated immunity, and neo-angiogenesis.
  • Changes in the peritoneal fluid adversely affect the spermatozoa.
  • Affected tubal motility and fallopian tube egg pick-up mechanisms, especially where pelvic scarring is significant.
  • Negative effects on uterine receptivity and implantation due to altered endometrial gene expression.

Co-existence of DIE and adenomyosis is associated with a 68% reduction in the likelihood of pregnancy. Endometriosis can also double the risk of miscarriage once the patient is pregnant. In addition, some couples are dealing with considerable sexual dysfunction related to pain, obviously affecting their ability to conceive.


Endometriosis is an inflammatory and scar-forming condition over-represented in the infertile population. Although many controversies exist, multiple mechanisms are at work that may reduce a couple’s fertility. Sometimes balancing the patient’s symptoms and her reproductive goals require careful consideration. At WA Gynaescope we believe that anyone presenting with longstanding infertility, unexplained infertility, or any symptoms of endometriosis warrant laparoscopic assessment for endometriosis. Current evidence is in favour of a more surgical approach to these patients.

Dr Sunny Baruah & Dr Gian Urbani