One of the most critical components of female fertility is ovarian reserve—the quantity and quality of the eggs remaining in the ovaries. Whether you’re trying to conceive now or considering future fertility, understanding your ovarian reserve is key. In this guide, we’ll explain what ovarian reserve means, how it’s tested, and what the results can tell you about your reproductive health.
What Is Ovarian Reserve?
Ovarian reserve refers to the number of viable eggs (oocytes) a woman has left in her ovaries. Women are born with all the eggs they will ever have—around 1 to 2 million at birth. By puberty, this drops to about 300,000–500,000, and only about 300–500 will mature and be ovulated during a woman’s reproductive years.
As you age, both the quantity and quality of your eggs decline, which can affect your chances of natural conception and your response to fertility treatments like IVF.
Why Test Ovarian Reserve?
Ovarian reserve testing is useful for:
- Women trying to conceive naturally without success
- Women considering egg freezing or IVF
- Women over 35 who want to assess their fertility
- Those with a family history of early menopause
- Individuals with conditions like endometriosis or PCOS
- Cancer patients preparing for treatment that may affect fertility
These tests help estimate how many eggs remain and how well your ovaries are functioning.
Key Ovarian Reserve Tests Explained
1. AMH (Anti-Müllerian Hormone)
- When tested: Any time during the menstrual cycle
- What it measures: AMH is secreted by small follicles in the ovaries. It reflects the number of eggs you have left.
- Normal range (may vary by lab):
- High (>4.0 ng/mL) – May indicate PCOS
- Normal (1.0–4.0 ng/mL) – Adequate ovarian reserve
- Low (<1.0 ng/mL) – Reduced ovarian reserve
Why it matters: AMH is considered the most accurate standalone marker of ovarian reserve. It’s especially helpful in predicting how you’ll respond to fertility medications in IVF cycles.
2. FSH (Follicle-Stimulating Hormone)
- When tested: Cycle days 2–4
- What it measures: FSH stimulates ovarian follicles to mature. As egg quantity declines, the brain compensates by increasing FSH levels.
- Normal range:
- <10 mIU/mL – Normal
- 10–20 mIU/mL – Borderline
- >20 mIU/mL – Poor ovarian reserve
Why it matters: High FSH levels indicate the ovaries are not responding well, signaling declining fertility. However, it can fluctuate and should be interpreted alongside estradiol levels.
3. Estradiol (E2)
- When tested: Cycle days 2–4, alongside FSH
- What it measures: Estradiol is a form of estrogen produced by developing follicles.
- Normal early-cycle range:
- <75 pg/mL – Ideal
- >80 pg/mL – May artificially suppress FSH, masking poor ovarian reserve
Why it matters: High early-cycle estradiol can indicate early follicular recruitment, a possible sign of diminished reserve. It’s especially important when interpreting borderline FSH levels.
4. Antral Follicle Count (AFC)
- When tested: Cycle days 2–5 via transvaginal ultrasound
- What it measures: The number of small (2–10 mm) follicles in both ovaries
- Normal range:
- 8–15 follicles total – Normal reserve
- <5 follicles – Low reserve
- >20 follicles – May indicate PCOS
Why it matters: AFC provides a visual estimate of how many eggs may be available in a given cycle. It’s also a strong predictor of ovarian response in IVF treatment.
5. Inhibin B
- When tested: Cycle days 2–4
- What it measures: A hormone produced by developing follicles that suppresses FSH.
- Why it matters: Lower levels can signal poor ovarian function. While less commonly used today due to AMH’s accuracy, it may still provide valuable context in some fertility assessments.
Interpreting Results: What Does It Mean for Your Fertility?
| Test | Normal | Abnormal | What It May Indicate |
|---|---|---|---|
| AMH | 1.0–4.0 ng/mL | <1.0 or >5.0 | Low: Diminished reserve, High: PCOS |
| FSH | <10 mIU/mL | >10–20 mIU/mL | High: Poor response to stimulation |
| Estradiol | <75 pg/mL | >80 pg/mL | High: May hide elevated FSH |
| AFC | 8–15 | <5 or >20 | Low: Fewer eggs, High: PCOS |
Ovarian Reserve vs. Egg Quality
It’s important to remember: ovarian reserve tests do not assess egg quality, which declines with age. A woman in her 40s may have a normal AMH but a higher likelihood of chromosomal abnormalities in her eggs, which affects implantation and miscarriage risk.
What Affects Ovarian Reserve?
Several factors influence ovarian reserve:
- Age (most significant factor)
- Genetics (e.g., early menopause in mother or sisters)
- Smoking
- Chemotherapy or radiation
- Endometriosis
- Ovarian surgery or cyst removal
Understanding these risks can help you decide when to test and whether fertility preservation (like egg freezing) is worth considering.
When Should You Consider Ovarian Reserve Testing?
You should consider testing if:
- You’re over 35 and trying to conceive
- You’ve had irregular cycles or trouble conceiving
- You’re planning to delay pregnancy
- You have a family history of early menopause
- You’re preparing for fertility treatment or egg freezing
What Happens After Testing?
Based on your ovarian reserve results, your doctor may:
- Recommend natural conception if results are reassuring
- Suggest ovulation induction, IUI, or IVF
- Counsel you on egg freezing if you’re not ready to conceive now
- Discuss using donor eggs in cases of severely diminished reserve
Final Thoughts
Ovarian reserve testing offers valuable insight into your fertility potential—but it’s just one part of the picture. It doesn’t guarantee whether you’ll get pregnant naturally or through treatment, but it can help guide informed decisions about timing, treatment, and family planning.
