Ovarian reserve is the number of eggs a woman has at birth. Ovarian reserve begins to decrease at age 30 and rapidly declines after age 40. Older age and decreased ovarian reserve are independent predictors of infertility. Diminished ovarian reserve (DOR) is a condition where a woman’s ovaries contain few eggs or eggs of a poor quality.
What causes diminished ovarian reserve?
Women with a decreased ovarian reserve are often born with fewer eggs than average, or they lose eggs more quickly than most women. Over time, the eggs may accumulate damage, decreasing their viability. Common causes of DOR include:
Age of 35 years or older
Chemotherapy and radiation treatments
Surgical removal of a portion or all of an ovary
What is premature ovarian failure?
DOR is not the same as premature ovarian failure (POF). With POF, menopause starts before the age of 40 years, and the cause is not known. However, POF may be associated immune disorders, chromosome problems, thyroid disorders, or lupus. Just as with DOR, ovarian failure impacts fertility, and when no eggs are released, conception cannot occur.
Why do some women lose fertility sooner than others?
The ovarian reserve is much like a biological clock. Some women remain fertile on into their 40s, whereas other women lose their fertility in their late 20s or 30s. Most women are born with around 2 million eggs, but every day, this number decreases. Eggs are lost even when a woman is on birth control or becomes pregnant.
What screening tests check egg quantity and quality?
Tests of ovarian reserve are screening tests used to evaluate quantity of remaining eggs. However, ovarian reserve testing does not tell us about the quality of the remaining eggs. These tests include:
Antral follicle count test – This involves counting the number of antral follicles that are visible using transvaginal ultrasound.
Day 3 FSH and E2 test – This involves measuring baseline follicle-stimulating hormone (FSH) and estradiol (E2) levels, which can give clues about menopause. When the woman is close to menopause, with a low ovarian reserve, the FSH level increases and estrogen levels reduced.
Clomiphene challenge test – This involves taking Clomid and assessing an FSH level.
Anti-Mullerian hormone (AMH) – Used by fertility specialists, AMH is used to evaluate the ovarian reserve.
How is decreased ovarian reserve treated?
Treatment options include:
Ovulation Induction with IUI Therapy – The first option for treatment of a diminished ovarian reserve is controlled ovarian hyperstimulation (COH) with intrauterine insemination (IUI). The stimulation involves use of hormone pills or injections that trigger the woman’s body to produce several mature eggs. Pelvic ultrasounds are used to monitor the eggs progression. The male partner’s sperm is injected into the uterus following COH. The sperm are prepared with a washing procedure to concentrate the specimen. Success using this treatment depends on the antral follicle count, ovarian reserve blood tests, and prior pregnancy history.
Injectable Gonadotropins for Ovarian Stimulation – To determine egg quality and quantity, the ovarian stimulation test helps determine the response of the ovaries. When given injectable FSH for ovarian stimulation, it predicts egg quantity and chances of successful infertility treatment.
In Vitro Fertilization – Women with decreased ovarian reserve can use in vitro fertilization (IVF) to achieve pregnancy. During an IVF cycle, the woman takes fertility injections on a daily basis. Once the eggs reach correct size (measured by ultrasound), they are surgically removed and fertilized in the laboratory setting. This treatment is used to stimulate multiple eggs per cycle to improve chances of high quality eggs. DOR may result from disease or injury, but it is essentially the result of normal aging. With IVF, the couple can use various assistive reproductive techniques to become pregnant.
Egg Freezing – Another option for women who have a declining egg reserve is to cryopreserve (freeze) eggs or embryos for future use. Through the IVF process, the embryos can be stored, and the couple can successfully deliver a baby when they choose. The prognosis for someone with DOR is guarded, and in the early stages, this condition reduces pregnancy chances and increases risks of miscarriage.
Donor Egg and IVF – Another popular option for women with DOR is IVF using donor eggs. This treatment uses the eggs from another woman to help the recipient female become pregnant. Donor eggs come from women aged 21 to 32 years, and are screened for quality and health. Egg donors can be known or anonymous, and the recipient couple is allowed to select their donor. Once the eggs are removed from the donor, they are fertilized with the recipient male’s sperm. Once embryos develop, they are placed in the recipient’s uterus using a minor procedure. Success rates for a live birth are high using egg donation.
Donor Embryos – Couples often donate embryos to other couples who are having trouble conceiving. This treatment involves use of donated frozen embryos to help the woman become pregnant. Embryos from donors are screened to make sure they are healthy and of high quality. Like egg donation, embryo donors can be known or anonymous. Success using embryo donation depends on the age of the couple donating the embryos.