Dr. Steve Vasilev, MD, Gynecologist, Endometriosis Surgeon*:
Hopefully this will help relieve the anxiety a bit.  If endo is suspected, endo can affect the diaphragm.  The diaphragm gets both motor and sensory supply from the phrenic nerve.  IF that nerve is irritated, by something like endo, the pain can “radiate” to certain predictable areas.  Most commonly people talk about pain at the tip of the shoulder, but actually this pain can radiate to anywhere in the shoulder region, including the shoulder blade.   This would be ever more likely if the pain is cyclic and mostly occurring during menses.

The caveat to the above is that endo can cause a LOT of things, but it can’t and does not cause everything.  So, something else may be irritating the phrenic nerve.   Having said that, the top of the list includes muscle strain, poor posture and spine nerve impingement, arthritis (do not have to be older to get this), sleeping positions and nerve stretch and other non-life-threatening conditions…..The C word is WAY lower on the list and usually goes along with lung malignancies (along with lung symptoms listed below) that irritate the phrenic nerve at the base of the lung where the diaphragm is.

The info above of course can’t replace a trusted physician-patient relationship and a full workup for all symptoms.  Generally, warning signs that something may be very wrong are things related to the heart and lung structure and function, like chest pain, shortness of breath, coughing up blood or very productive cough, sudden leg swelling (blood clot that can travel to the lungs) and more.  So, please have your doc review all of this with you or….if you get a blank stare and assurances that this can’t be related to endo …..get a second opinion.

*This is not medical advice and is aimed for informational use only. Don’t hesitate to get in touch with the doctor’s office or consult your doctor for any medical questions.