Written and medically reviewed by Dr Karen Joash, Consultant Obstetrician and Gynaecologist | Last reviewed: August 2026
The short answer
Egg quality and ovarian reserve both decline with age, and this becomes more marked after 35. The decline is real but not uniform — many women conceive naturally or with support after 35 and beyond. No supplement has been shown to reverse age-related egg decline, but adequate nutrition, a healthy weight, avoiding smoking and limiting alcohol remain priorities. Some evidence exists around supplements which support ovarian health such as Coenzyme Q10.
What do we mean by egg quality?
Egg quality broadly refers to the likelihood that an egg, once fertilised, will develop into a healthy embryo and result in a pregnancy. Poor quality is often linked to chromosomal errors, which become more common as eggs age. This is why miscarriage rates rise and IVF success rates fall with increasing maternal age.
Ovarian reserve — the number of eggs remaining — is separate from quality but both matter for fertility. Tests such as AMH and antral follicle count give information about reserve, not quality directly.
How does age affect fertility after 35?
Fertility begins to decline in the early thirties and more steeply after 35. This reflects both falling egg numbers and a higher proportion of chromosomally abnormal eggs. The change is gradual rather than a cliff edge at a single birthday.
Many factors influence individual fertility: cycle regularity, tubal health, partner factors, weight, thyroid function, conditions such as PMOS and previous treatment. Age is one important variable, not the only one.
What does the nutrition evidence show?
No food or supplement has been proven to restore egg quality lost through ageing. However, nutritional adequacy is a reasonable foundation for reproductive health. A varied diet with sufficient folate or folic acid, iodine, vitamin D, omega-3 and iron supports overall health and reduces the risk of deficiency during early pregnancy.
Coenzyme Q10 is widely discussed in fertility circles. Some small studies suggest benefit on certain IVF measures and egg quality.
Lifestyle factors with evidence
Smoking is associated with earlier ovarian ageing and should be stopped. A high BMI or very low body weight can affect ovulation. Alcohol should be limited when trying to conceive. Sleep, stress management and treating underlying conditions such as thyroid disease or PMOS are all relevant to reproductive health.
When to seek a fertility assessment
If you are under 35 and have been trying to conceive for 12 months without success, or over 35 and have been trying for six months, ask your GP for an initial assessment. Seek earlier review if you have irregular periods, a history of PMOS, endometriosis, pelvic infection or previous cancer treatment, or if your partner has known fertility concerns.
Fertility investigations can include cycle assessment, hormone tests, tubal assessment and semen analysis. Early review increases the range of options available.
What to ask a fertility clinic
Ask about AMH, antral follicle count, the clinic's live birth rates for your age group, what investigations are recommended before treatment, and whether lifestyle changes are likely to affect your specific situation. Be cautious about clinics that make large promises based on supplements or unvalidated tests.
Frequently asked questions
Can I improve egg quality naturally?
You cannot reverse age-related chromosomal changes, but optimising nutrition, avoiding smoking, limiting alcohol and managing weight and underlying conditions are evidence-based steps worth taking.
Is CoQ10 worth taking for fertility?
The evidence suggest yes
Does stress affect egg quality?
Severe or prolonged stress may affect hormonal regulation, but the direct effect on egg quality is not well established. Sleep and stress support are reasonable health goals regardless.
A PurerVita note
PurerVita supports evidence-led choices across women's hormonal, metabolic and reproductive health. Supplements can complement food and clinical care; they do not diagnose or treat medical conditions. Seek personalised advice for symptoms, pregnancy plans, medicines or abnormal test results.
If you are supporting your ovarian health through perimenopause, PCOS/PMOS or fertility, explore The O Capsule — PurerVita's multivitamin formulated for ovarian health.
Explore PurerVita's evidence-led support for women's health.
Sources
- NHS: Infertility
- NICE: Fertility problems assessment and treatment
- NHS: Trying to get pregnant
- HFEA: Fertility treatment statistics