“Ovarian Reserve” is a term referred by many infertility specialists to describe the size, quality and developmental potential of the eggs remaining in the ovary. As a woman ages ovarian reserve diminishes along with the chance of a chromosomal abnormal egg which increases the potential for miscarriage. As a result, older women are less likely to become pregnant and are progressively more likely should they become pregnant to have a miscarriage. Many patients ask us “how quickly does ovarian reserve diminish?”?
The Facts About Ovarian Reserve and Your Fertility
- Approximately 13% of women under age 35 desiring pregnancy will have difficulty having a baby and a similar percentage of those pregnant will have a miscarriage.
- While 25% of women age 35-39 will have difficulty conceiving, by the age of 40, 34% of women attempting pregnancy will have difficulty and approximately 26% of those over age 40 who are pregnant will have a miscarriage.
How quickly does ovarian reserve diminish?
In some women, ovarian reserve and fertility decreases earlier than expected. Predisposing factors include smoking, endometriosis involving the ovary, ovarian surgery, chemotherapy, and radiation. Some women may have a genetic predisposition, suggested by their mother’s or their sister’s early menopause or related to being a carrier for Fragile X. In most women, no cause for diminished ovarian reserve can be identified. Alterations in menstrual cycle length may be one of the earliest indicators of reproductive aging, but most women with decreased reserve have no change in their menstrual pattern.
How is diminished ovarian reserve diagnosed?
The simplest and most common “ovarian reserve” test is determination of a hormone made in the pituitary gland called follicle stimulating hormone (FSH) which is as the name suggests a hormone that is secreted to induce the ovary to make a follicle leading to a mature (ready to be fertilized) egg.
The concentration of FSH in the serum is obtained by blood work is ideally on the 2nd, 3rd, or 4th day following the onset of menstrual flow. In most laboratories, FSH values greater than 10-15 IU/L are thought suggestive of diminished ovarian reserve. The serum estradiol concentration, obtained concurrently with FSH is also important since elevated levels (>75-80 pg/mL) may lower FSH concentrations below values that would otherwise suggest diminished ovarian reserve.
Some fertility physicians use the clomiphene citrate challenge test (CCCT) as a method to assess ovarian reserve by measuring the serum FSH level again on cycle day 10 after taking 100 mg/day of clomiphene citrate (Clomid, Serophene) on cycle days 5-9. An abnormally elevated cycle day 2-4 FSH or estradiol concentration or stimulated (cycle day 10) FSH level (>10-15 IU/L) suggests diminished ovarian reserve. Perhaps the best test to assess ovarian reserve is by measuring serum levels of Antimullerian Hormone (AMH).
What does AMH mean for your fertility?
AMH is produced by granulosa cells surrounding each oocyte in the developing ovarian follicle. It is produced primarily by the preantral and small (less than 8 mm) antral follicles in the ovary. Since these follicle numbers decline with age the production and serum levels of AMH at any given time are reflective of a woman’s ovarian reserve. AMH is not predictive of pregnancy but is predictive of a woman’s response to gonadotropin stimulation with the lower the AMH the lower the ovarian reserve and thus the higher the dose of medication needed to try and achieve a mature oocyte at the time of oocyte retrieval with IVF.
Can you get pregnant with a diminished ovarian reserve?
Ovarian reserve testing has some value for predicting ovarian response to fertility treatments (ovarian stimulation) and may help in planning therapy (ovulation induction for IUI or IVF). An abnormal test result may suggest decreased probability of success, but does not absolutely predict failure. Ovarian reserve testing does provide important information, but age and previous fertility or response to gonadotropin therapy (FSH, LH, hMG stimulation) have greater relevance and predictive value. Women with mildly abnormal results may have a lower fertility potential but they are not sterile. Therefore like all test results they should be interpreted, explained, and applied with caution, sensitivity and compassion.
This article was originally published on Fertility Centers of New England by Joseph A. Hill, III, M.D. Board-Certified in Reproductive Endocrinology and Infertility