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Decreased Ovarian Reserve (DOR)


Robert W. Rebar

, MD, Western Michigan University Homer Stryker M.D. School of Medicine

Last full review/revision Sep 2020| Content last modified Sep 2020
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Decreased ovarian reserve is a decrease in the quantity or quality of oocytes, leading to impaired fertility.

Ovarian reserve may begin to decrease at age 30 or even earlier and decreases rapidly after age 40. Ovarian lesions also decrease reserve. Although older age is a risk factor for decreased ovarian reserve, age and decreased ovarian reserve are each independent predictors of infertility and thus of a poorer response to fertility treatment. However, decreased ovarian reserve does not mean that pregnancy is impossible.

Diagnosis of Decreased Ovarian Reserve

  • Follicle-stimulating hormone (FSH) and estradiol levels for screening

  • Antimüllerian hormone (AMH) level and/or antral follicle count (AFC)

(See also Testing and interpreting measures of ovarian reserve: A committee opinion, from the Practice Committee of the American Society for Reproductive Medicine and the American Society for Reproductive Medicine.)

Testing for decreased ovarian reserve is considered for women who

  • Are ≥ 35

  • Have had ovarian surgery

  • Have responded poorly to treatments such as ovarian stimulation with exogenous gonadotropins

Measuring FSH or estradiol levels is useful as a screening test for decreased ovarian reserve. FSH levels > 10 mIU/mL or estradiol levels < 80 pg/mL on day 3 of the menstrual cycle Menstrual Cycle Hormonal interaction between the hypothalamus, anterior pituitary gland, and ovaries regulates the female reproductive system. The hypothalamus secretes a small peptide, gonadotropin-releasing... read more suggest ovarian reserve is decreased. However, the AMH level and AFC are currently the best tests for diagnosing decreased ovarian reserve.

The AMH level is an early, reliable predictor of declining ovarian function. Increasingly, AMH measurement is used to assess ovarian reserve. A low AMH level predicts a lower chance of pregnancy after in vitro fertilization In vitro fertilization (IVF) Assisted reproductive techniques (ARTs) involve manipulation of sperm and ova or embryos in vitro with the goal of producing a pregnancy. ARTs may result in multifetal pregnancy, but risk is... read more In vitro fertilization (IVF) (IVF); pregnancy is rare when the level is too low to be detected.

The AFC is the total number of follicles that measure 2 to 10 mm (mean diameter) in both ovaries during the early follicular phase; AFC is determined by observation during transvaginal ultrasonography. If AFC is low (3 to 10), pregnancy after IVF is less likely.

Treatment of Decreased Ovarian Reserve

  • Sometimes use of donor oocytes

Because pregnancy may still be possible, treatment of decreased ovarian reserve is individualized based on the woman's circumstances and age.

If women are > 42 or if decreased ovarian reserve is diagnosed, assisted reproduction using donor oocytes, if available, may be necessary.

Key Points

  • Ovarian reserve may begin to decrease at age 30 or even earlier and decreases rapidly after age 40.

  • Begin testing for decreased ovarian reserve by measuring FSH or estradiol levels, but measure antimüllerian hormone (AMH) level and/or antral follicle count (AFC) to confirm the diagnosis.

  • If women are > 42 or ovarian reserve is decreased, consider assisted reproductive techniques using donor oocytes.

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