The diagnosis of low ovarian reserve (LOR) often causes concern for individuals trying to conceive, as it indicates a reduced pool of eggs remaining in the ovaries. This condition reflects a decline in the quantity of reproductive cells available for fertilization, raising questions about the possibility of pregnancy. While the total number of eggs is lower than expected for one’s age, LOR does not mean the complete absence of reproductive potential. The journey to conception may require different approaches, but achieving a healthy pregnancy remains possible.
Defining and Measuring Low Ovarian Reserve
Low ovarian reserve (LOR) describes a diminished supply of ovarian follicles, the structures that house immature eggs. This decline occurs naturally with age, but can be accelerated by genetics, prior surgery, or certain medical treatments. LOR testing primarily estimates how the ovaries will respond to fertility medications.
Physicians rely on three main tests for diagnosis. The Anti-Müllerian Hormone (AMH) blood test is a reliable marker produced by growing follicles, and its level remains stable. A low AMH level, often below 1.0 ng/mL, suggests a significantly reduced egg supply.
The Follicle-Stimulating Hormone (FSH) test is typically drawn on the third day of the menstrual cycle. A high day-three FSH level, generally above 10 mIU/mL, indicates the pituitary gland is working harder to stimulate the ovaries, suggesting a low reserve.
The third measure is the Antral Follicle Count (AFC), which uses a transvaginal ultrasound to count the tiny follicles in both ovaries. An AFC totaling fewer than five to seven follicles often correlates with a low reserve.
Natural Conception Possibility
Low ovarian reserve does not eliminate the possibility of conceiving without medical assistance. LOR primarily reflects a reduced quantity of eggs, and only a single viable egg is required for a spontaneous pregnancy. Individuals who maintain regular menstrual cycles are still successfully recruiting and ovulating an egg each month.
The probability of conception per cycle is typically lower for those with diminished reserve compared to those with an age-appropriate egg supply. Fewer follicles are available to be recruited, which can shorten the overall reproductive lifespan. Unassisted conception remains a realistic outcome, especially if the individual is younger and has no other fertility issues.
The standard LOR tests are poor predictors of natural pregnancy potential. These markers are highly effective at predicting the ovarian response to stimulation drugs, but they do not measure egg quality directly. For women ovulating regularly, the focus remains on the quality of the few eggs remaining, which is primarily a function of age.
Assisted Reproductive Options
When natural attempts are unsuccessful or the reserve is severely limited, assisted reproductive technologies offer effective pathways to pregnancy. Intrauterine Insemination (IUI) is sometimes attempted first in cases of mild LOR, involving placing concentrated sperm directly into the uterus during ovulation. IUI success rates are modest, often in the single digits per cycle, and are typically combined with mild ovarian stimulation to increase the number of available eggs.
In Vitro Fertilization (IVF) is generally the most effective treatment for LOR, although success rates are lower than for those with a normal reserve. IVF protocols are tailored for low responders, utilizing approaches like micro-dose flare or antagonist protocols to maximize the retrieval of available eggs. The challenge is the low yield of mature eggs, which may necessitate multiple cycles to bank enough embryos for a successful transfer.
When autologous IVF (using one’s own eggs) is unlikely to succeed due to severely diminished reserve or poor egg quality, oocyte donation is a highly successful alternative. This method bypasses the patient’s ovarian reserve issue by using eggs from a younger, screened donor. Success rates for IVF with donor eggs are significantly higher, often reaching 50% to over 60% per transfer cycle, determined primarily by the donor’s egg quality and the recipient’s uterine health.
Prognostic Factors for Success
The variable that most significantly influences the outcome for individuals with low ovarian reserve is maternal age. Age is the most reliable proxy for egg quality, which determines whether an egg can be successfully fertilized and develop into a healthy embryo. A younger person with a low AMH level often has a much higher chance of success, both natural and assisted, than an older person with the same low AMH level.
The severity of the LOR test results also modifies the prognosis by predicting the response to fertility treatment. A severely low AMH, such as below 0.5 ng/mL, predicts a very poor response to ovarian stimulation and a low chance of pregnancy using one’s own eggs. Similarly, a consistently elevated Day 3 FSH level over 15 mIU/mL suggests diminished reproductive capacity and a higher likelihood of cycle cancellation during IVF.
Younger women, even those classified as poor responders in IVF, often maintain a preserved chance of pregnancy compared to older women with the same LOR markers. This underscores that while LOR tests predict the number of eggs retrieved, age remains the dominant indicator of the biological quality of those eggs. Therefore, a personalized treatment strategy prioritizing the impact of age is often recommended.