DOR stands for diminished ovarian reserve, a condition where a woman’s ovaries have fewer eggs remaining than expected for her age. It doesn’t mean you can’t get pregnant, but it does mean the pool of eggs available for fertilization is smaller, which can make conception harder and affect how well fertility treatments work.
The term comes up most often during fertility testing, when blood work or an ultrasound reveals that egg supply is running lower than typical. Understanding what DOR actually means, what causes it, and what your options look like can help you make sense of a diagnosis that often feels more alarming than it needs to be.
What Ovarian Reserve Actually Measures
Every woman is born with a fixed number of eggs. Unlike sperm, which are produced continuously, eggs can’t be replenished. Over time, that supply declines naturally. By the time menopause arrives, the reserve is essentially depleted. Ovarian reserve is simply a snapshot of where you are in that process.
The two most common ways to measure it are a blood test for AMH (anti-Müllerian hormone) and a transvaginal ultrasound that counts small follicles on each ovary, called an antral follicle count. AMH is produced by developing follicles, so lower levels suggest fewer eggs remain. An AMH below 1.0 ng/mL is generally considered low, and below 0.7 ng/mL is often used to define DOR in research settings.
One important distinction: ovarian reserve reflects egg quantity, not egg quality. A low AMH doesn’t tell you whether the eggs you have left are healthy. Egg quality is primarily tied to age, not to reserve markers. This is why a 28-year-old with low AMH may still have good odds of conceiving with the eggs she has, while a 42-year-old with normal AMH may face challenges related to egg quality instead.
Signs You Might Notice
DOR often produces no obvious symptoms, which is part of why it catches many women off guard. The most common physical sign is shorter menstrual cycles. Research tracking women’s cycles found that those with low AMH had periods arriving roughly 1.7 days sooner than women with normal levels. They were also about 1.6 times more likely to have cycles shorter than 21 days. If your previously regular 28-day cycle has gradually shortened to 24 or 25 days, that shift could reflect declining ovarian reserve.
Some women also notice lighter periods or changes in flow, though these are less reliable indicators. Many women with DOR have completely normal-seeming cycles and only discover the issue through routine fertility bloodwork.
Causes Beyond Age
Age is the most common reason for diminished ovarian reserve, but it’s not the only one. DOR can show up in women in their 20s and 30s, sometimes with no clear explanation. When there is an identifiable cause, it typically falls into a few categories.
Genetic Factors
The strongest known genetic link is to the FMR1 gene, the same gene associated with Fragile X syndrome. Women who carry a “premutation” version of this gene (a specific expansion in the gene’s structure) tend to experience earlier ovarian aging, with higher FSH levels and shorter follicular phases. Studies have found that roughly 14% of women with DOR carry these intermediate or premutation-range gene changes, compared to only about 4% of women without DOR.
Autoimmune Conditions
The immune system can sometimes target ovarian tissue. Research in animal models has shown that certain autoimmune gene defects lead to immune cells infiltrating the ovaries, with 96% of affected mice showing this infiltration by 20 weeks of age. In humans, the connection between autoimmunity and DOR is less clearly established than it is for complete ovarian failure, but several studies suggest a link, particularly in women who also have other autoimmune conditions.
Medical Treatments
Ovarian surgery, chemotherapy, and radiation can all reduce ovarian reserve directly by destroying follicles or damaging ovarian tissue. This is one of the more predictable causes and is something oncologists increasingly discuss with younger patients before starting cancer treatment.
There’s also evidence that environmental chemical exposure can accelerate follicle loss and reduce egg quality, though pinpointing which exposures matter most is still an active area of investigation.
What DOR Means for Getting Pregnant
A DOR diagnosis can feel devastating, but the picture is more nuanced than many women expect. Two large studies tracked women trying to conceive naturally and found something surprising: women with low AMH (below 0.7 ng/mL) had similar pregnancy rates after 6 and 12 months of trying compared to women with normal levels. One of those studies, called the Time to Conceive study, followed 750 women aged 30 to 44, and the other tracked over 1,200 women aged 18 to 40. In both, low ovarian reserve markers did not predict lower chances of natural conception.
The American Society for Reproductive Medicine has specifically stated that ovarian reserve tests should not be used as a fertility test for women who aren’t already experiencing infertility, and that low values should not be used to refuse treatment. The tests are better at predicting how many eggs you’ll produce during IVF stimulation than whether you’ll actually get pregnant.
Where DOR does matter significantly is in fertility treatment response. During IVF, fewer eggs typically means fewer embryos to work with, which reduces your chances per cycle and limits how many cycles are likely to be productive.
IVF With Diminished Ovarian Reserve
Standard IVF protocols are designed to stimulate the ovaries into producing multiple eggs at once. When your reserve is low, the ovaries simply don’t respond as robustly to those medications. Fertility specialists adjust their approach in several ways.
The most straightforward change is modifying the stimulation protocol. Long suppression protocols, where the ovaries are quieted before stimulation, tend to be counterproductive for women with DOR because they suppress an already limited response. Instead, doctors typically use shorter protocols, sometimes called microdose flare or short-flare protocols, that work with the body’s own hormonal surge rather than suppressing it. Interestingly, research has shown that simply increasing medication doses beyond a certain point doesn’t improve results. Studies comparing moderate and high doses of stimulation drugs found no meaningful difference in outcomes for poor responders.
A more recent approach called double stimulation, or the Shanghai protocol, retrieves eggs twice in the same menstrual cycle by stimulating follicles during both the follicular and luteal phases. This can help accumulate embryos more quickly when time feels limited.
Other modifications include adding medications that block estrogen to recruit more follicles, or using hormone priming before a stimulation cycle begins. Some clinics also offer natural or mini-IVF cycles that work with whatever follicles the body produces on its own, rather than trying to force a larger response.
Realistic Success Rates
The numbers for IVF with low ovarian reserve are lower than for other types of infertility, and it’s worth understanding what that looks like in practice. One institutional study found that women with low ovarian reserve had a cumulative live birth rate of about 29% across multiple IVF cycles. For comparison, women with other causes of infertility at the same center had cumulative rates between 65% and 72%.
Perhaps more importantly, most of the benefit came in the first two cycles. After that, the cumulative rate plateaued, improving by only about 7% with additional attempts before leveling off entirely around the sixth cycle. This suggests that for many women with DOR, the first two or three IVF cycles provide the clearest picture of whether treatment is likely to succeed with their own eggs.
Supplements: DHEA and CoQ10
Two supplements come up repeatedly in conversations about DOR: DHEA (a hormone precursor) and CoQ10 (an antioxidant involved in cellular energy production). Both are widely used, and there is some supporting evidence.
A meta-analysis of studies on oral supplements for women with DOR found that supplementation increased the number of eggs retrieved by roughly one additional egg per cycle and improved both the number and rate of high-quality embryos. Subgroup analysis suggested that CoQ10 alone was more effective than DHEA alone.
Dosing varied across studies. DHEA was most commonly used at 75 mg daily (often split into three 25 mg doses). CoQ10 dosing ranged more widely, with 200 mg three times daily and 300 mg daily being among the more common regimens studied. These are typically started two to three months before an IVF cycle to allow time for follicles to develop under their influence.
When Donor Eggs Make Sense
For women whose IVF cycles with their own eggs aren’t producing viable embryos, donor eggs are an alternative that bypasses the ovarian reserve issue entirely. Because donor eggs come from younger women with normal reserves, pregnancy rates are substantially higher. One retrospective study found a 43% positive pregnancy rate per cycle with donor eggs, compared to about 28% with the patient’s own eggs.
The decision to move to donor eggs is deeply personal and depends on factors beyond statistics: how important genetic connection is to you, your age, your emotional and financial capacity for additional cycles, and how your body has responded to treatment so far. Many women try one to three cycles with their own eggs before considering this option, which aligns with the data showing that the benefit of additional own-egg cycles diminishes after the second or third attempt.