What is ovarian reserve and how do you test it?

What Is Ovarian Reserve and How Do You Test It?

5 min read

If you’re trying (or thinking about trying) to conceive, you probably feel hyper-aware of your biological clock. Unfortunately, that tick-tock is real. As you age your egg quality and quantity decrease, giving you a pool to work with that’s both smaller and less healthy. 

Ovarian reserve is not the only indicator of fertility (and it alone can’t tell you whether or not you can become pregnant since it’s not a marker of egg quality), but knowing more about your egg quantity can help you make decisions about your reproductive timeline, including trying to conceive sooner or seeking out medical support earlier. Read on to learn more about your ovarian reserve, what it means, and how you can test it.

What is ovarian reserve?

When you’re born, your ovaries already contain all the eggs you will ever have. Ovarian reserve refers to the number of eggs left in this pool, and that number decreases with age. Age is the strongest predictor of egg quantity (ovarian reserve) and it’s the most common reason for diminished ovarian reserve (DOR—more on that here). Diminished ovarian reserve is one clinical infertility diagnosis, but it doesn’t mean you can’t get pregnant spontaneously.

Egg quality vs. eqq quantity  →

Understanding your ovarian reserve provides you with more insights into your reproductive health, impacting your reproductive timeline (when you have kids and how many you have) and how successful treatment can be (if there are no or few eggs to retrieve, your IVF chances may be lower). Remember that quantity is just one part of conception—quality (the health of the egg) is just as important. 

Egg count by age (on average):

  • At  5 months gestation (yes, before you’re born!): about 5 million eggs

  • At birth: about 1 million eggs

  • At puberty: 300,000 to 400,000 eggs

  • During your reproductive years: About 120,000 at age 30 and 25,000 at 38 (a pretty sharp decline)

  • At menopause: About 1,000 eggs left (though they don’t have capacity to mature for ovulation)

How do I test my ovarian reserve?

There are several ways to get more information about your egg count.  

1. Cycle Day 3 FSH Test

FSH (follicle-stimulating hormone) is secreted from the brain to the ovaries and (as the name suggests) stimulates the development of follicles during the early part of the menstrual cycle. FSH is an essential hormone for supporting ovulation, regular menstrual cycles, and fertility.

FSH can be measured in the blood with a blood draw (requested by your doctor) or in the urine (which can be done at home—more on that in a sec). In both cases, FSH needs to be tested early in the cycle (on days 2 to 5, with day 1 being the first full day of bleeding). If the test shows FSH levels greater than 10 mIU/mL, it can be a flag for reduced ovarian reserve and you can opt to pursue futher testing to learn more and consider other fertility-focused investigations. Generally speaking, the higher the FSH the lower the ovarian reserve.

Bird&Be’s Ovarian Reserve Screening Test is an at-home urine test (no doctor’s requisition needed) that measures your FSH and can help screen for diminished ovarian reserve. There are 6 strips so you can test on days 3, 4, and 5, over 2 cycles and flag any high-FSH results with your doctor.

2. AMH Test

AMH (anti-mullerian hormone) is a hormone secreted by developing follicles—the greater the number of follicles developing that cycle, the higher the AMH. AMH is consistent over the menstrual cycle and does not need to be tested on a specific day (unlike FSH) and testing is typically done with a blood test from your doctor. For females, AMH naturally decreases as we age (see a theme, here?), and it doesn’t predict the chances of spontaneous conception or live birth rates once pregnant. But, it is an important predictor of your ovaries' response to fertility medication and IVF success. The lower the AMH, the lower the ovarian reserve.

3. Antral Follicle Count Test

You can also assess ovarian reserve by looking at the ovaries with an ultrasound. A transvaginal ultrasound is used to look at the ovaries and the antral follicles within the ovaries that have been recruited for that cycle. The follicles are counted and the total number in both ovaries provides the antral follicle count (AFC). The lower the number of follicles, the lower the ovarian reserve. A low antral follicle count (less than 6) is linked to diminished ovarian reserve and poor ovarian response in IVF. This test is typically only done at fertility clinics so isn’t as accessible to those who aren’t currently undergoing fertility treatment. Because this test relies on visual evidence (including the accuracy of the person counting, and the quality of the ultrasound machine) the results are often considered more subjective than other tests, though when combined with AMH or FSH is a helpful piece in considering ovarian reserve. 

Can you improve or increase ovarian reserve?

Because low ovarian reserve is usually the result of aging, there’s not a lot you can do to change it. But, some things can hasten the depletion (like smoking, environmental exposures, and Vitamin D deficiency). By making some lifestyle changes, you may be able to slow or stabilize the loss of eggs. But, currently there are no medical interventions that have been proven to increase your existing egg count.

4 Simple Lifestyle Changes to Boost Your Fertility →

Does low ovarian reserve mean early menopause?

Ovarian reserve decreases until you reach menopause. Having a low ovarian reserve suggests you’re closer to menopause, but on its own does not predict early menopause. An ovarian reserve test is just a snapshot of what’s going on with the total ovarian pool at the time of the test and can’t determine the rate of loss. When you haven’t had a period for 12 consecutive months, you’ll likely be diagnosed with menopause (and the transition period leading up to menopause is called perimenopause, which can last several years and usually involves irregular cycles and hormonal fluctuations). When multiple ovarian reserve tests (like FSH, AMH, and an antral follicle count) are combined, and age is considered, there’s a better idea of the progression to menopause. 

Can you conceive with a low ovarian reserve?

It's important to remember that a low ovarian reserve doesn’t mean you can’t conceive. It takes just one good-quality egg to meet up with one good-quality sperm to create a viable embryo. In a non-medicated cycle, only one egg (usually) ovulates, so having a higher or lower reserve doesn’t impact your chances of conceiving spontaneously. (Though it’s important to keep in mind that the longer you wait, the smaller that reserve is likely to be—something to consider if you’re hoping to have multiple kids.) A larger reserve of eggs gives you more chances (especially when pursuing treatments like IVF), but just as important is the health of those eggs, and, luckily, there are things you can do to improve egg quality (for example, taking a good quality and antioxidant-packed prenatal at least 3 months before trying to conceive—like The Power Prenatal for Females).