Diminished Ovarian Reserve (DOR)

Diminished Ovarian Reserve (DOR) means the ovaries have fewer eggs left than expected for a woman's age. Egg quality is often lower as well. DOR is most often linked to age, but it can also occur early. Early causes include past ovarian surgery, autoimmune disease, endometrioma, and genetic factors. They also include past treatments that harm the ovaries (gonadotoxic treatment).

DOR does not make pregnancy impossible. It does make timely action more urgent. It also makes the cause of the low reserve more important to identify.¹

Clinicians assess DOR with three markers read together, never one alone. The first is a blood test for anti-Müllerian hormone (AMH). The second is an ultrasound antral follicle count (AFC). The third is FSH on cycle day 3. No single marker gives a firm answer.

A 2017 JAMA study examined women ages 30 to 44. It found no significant association between AMH, FSH, or inhibin B levels and reduced fertility. The study's own authors warn against using these markers as tests of natural fertility.² A low reserve value does not predict whether a woman can conceive naturally. It should never serve as grounds to tell her that pregnancy is out of reach, or to steer her toward IVF.

In restorative reproductive medicine, a DOR diagnosis is a reason to look deeper. Clinicians look for causes that can be treated. These include autoimmune activity, endometrioma, thyroid disorders, oxidative stress, and low levels of key nutrients. One review examined two family medicine clinics that practice restorative reproductive medicine. It found DOR in 12% of the patients they evaluated.³

See Ovarian Reserve for how to interpret reserve markers in context. See DHEA supplementation for one studied way to support women with DOR.