Diminished Ovarian Reserve (DOR)

Diminished Ovarian Reserve (DOR) is a reduction in the quantity and, often, the quality of the remaining egg supply in the ovaries relative to what is expected for a woman's age. DOR is most commonly age-related, but it can occur prematurely due to prior ovarian surgery, autoimmune conditions, endometrioma, genetic factors, or prior gonadotoxic treatment. It does not make pregnancy impossible. A DOR diagnosis makes it more urgent to act, and more important to understand why reserve is low.¹

DOR is assessed through three markers used together, not in isolation: serum anti-Müllerian hormone (AMH), antral follicle count (AFC) on ultrasound, and cycle day 3 FSH. No single marker is definitive. A 2017 JAMA study found no significant association between AMH, FSH, and inhibin B levels and reduced fertility in women ages 30 to 44. The study's own authors caution against using these biomarkers as tests of natural fertility.² A low reserve number does not predict whether a woman can conceive on her own, and it should never be used to tell her that conception is out of reach or to route her toward IVF.

In RRM, a DOR diagnosis prompts investigation, not resignation. Clinicians evaluate for treatable contributors: autoimmune activity, endometrioma, thyroid dysfunction, oxidative burden, and nutritional deficiencies. A diagnostic frequency review of two family medicine clinics practicing restorative reproductive medicine identified DOR in 12% of patients evaluated.³ See Ovarian Reserve for interpretation of reserve markers in clinical context and DHEA supplementation for one studied supportive strategy in DOR.