Infertility is one of the big tip-offs of endometriosis. Although pain is a famous component, some cases of endometriosis have no pain at all. There are two main routes of infertility at the hands of endometriosis. One, as mentioned above, is the inflammatory and humoral disruption of a conception-friendly environment. The other is adhesion formation that may kink a fallopian tube or put up a mechanical barrier between the ovulating ovary and the tube which would normally carry the egg toward conception at mid-tube.
Endometriosis is a terrible disease for many reasons.
The pain and suffering, and the depriving a couple of children is one thing. The other thing is that it is a surgical diagnosis. He or she can say a patient may have it, but the actual determination has to be based on seeing it in the abdomen or pelvis. If the doctor is too conservative, not enough laparoscopy will be done and too many undiagnosed cases of endometriosis will be allowed to continue on damaging a woman's reproductive chances. It's a difficult fine line to negotiate, and most doctors over the years narrow that line to a point that is comfortable for them.