Is it harder to get pregnant after 35 and can nutrition help?

Is it harder to get pregnant after 35 and can nutrition help?

Yes, fertility does naturally decline with age, and this is a biological reality worth understanding honestly. But here is what too few women are told: the rate of that decline is not fixed, the factors that drive it are partly modifiable, and nutrition is one of the most powerful tools available for supporting egg quality, hormonal health, and reproductive function as you move through your mid-thirties and beyond. Age is not the only variable in this equation.

What actually changes after 35

You are born with all the eggs you will ever have. From birth onwards, that supply gradually diminishes, and the quality of the remaining eggs also changes over time. The primary mechanism behind this is a decline in mitochondrial function within the egg cells, combined with an increase in oxidative stress, both of which make it more likely that eggs will have chromosomal abnormalities that prevent healthy fertilisation, implantation, or development.

According to the American Society for Reproductive Medicine, by the age of 30 a healthy, fertile woman has approximately a 20% chance of conceiving each month of trying. By age 40, that figure falls to around 5% per month. Miscarriage risk also rises with age, from approximately 20% at age 35 to around 33 to 40% by age 40, primarily due to the increased rate of chromosomal abnormalities in eggs.

Natural conception rates, while lower, remain clinically relevant after 35. A systematic review and meta-analysis found that for a 35-year-old woman with two years of unexplained infertility, the predicted probability of natural conception leading to an ongoing pregnancy was 15% over six months and 28% over twelve months. This is not negligible, and it is a reason why nutritional optimisation in this window matters enormously.

Why this is not the whole story

Age affects egg quantity. Nutrition, lifestyle, and targeted supplementation affect egg quality. And egg quality is ultimately what determines whether fertilisation succeeds, whether an embryo develops normally, and whether a pregnancy is sustained.

The eggs developing in your ovaries right now began their maturation process approximately 90 days ago. This means that what you eat, how you manage stress, what you supplement with, and how you protect your body from oxidative damage today is directly influencing the eggs that will be available to you three months from now. That 90-day window is one of the most important concepts in fertility nutrition for women over 35.

The role of CoQ10

CoQ10 is the most well-researched nutrient for age-related fertility decline, and the science is compelling. CoQ10 levels in the body naturally decrease from around age 35, at exactly the same time that egg quality begins to decline more rapidly. This is not a coincidence. Research has shown that this age-related reduction in CoQ10 is accompanied by mitochondrial dysfunction in the egg, reduced ATP production, and increased chromosomal abnormalities.

Landmark research published in Cell Metabolism demonstrated that the age-related decline in oocyte quality could be reversed by CoQ10 supplementation in animal models, with mitochondrial function restored to levels seen in younger subjects. In human clinical studies, women with poor ovarian reserve who took CoQ10 prior to IVF produced more mature eggs, had higher fertilisation rates, more high-quality embryos, and significantly fewer cancelled cycles due to poor embryo development compared to control groups.

Clinical evidence now supports that women aged 35 and older may benefit from CoQ10 supplementation specifically to counteract the age-related decline in endogenous CoQ10 synthesis, restore mitochondrial function in oocytes, and reduce chromosomal abnormalities in developing eggs. Supplementing with CoQ10 is seen as one of the most evidence-based ways to counteract these age-related declines in fertility, according to researchers at Oxford University.

Omega-3 fatty acids and the ageing ovary

Research published in PMC demonstrated that a lifelong diet rich in omega-3 fatty acids, particularly DHA, maintained ovarian follicle reserves and oocyte quality at advanced maternal age. The Western diet, which is dominant in omega-6 fats and low in omega-3s, creates a nutritional environment that accelerates ovarian ageing. Correcting this imbalance through oily fish, flaxseed, walnuts, and high-quality omega-3 supplementation is a foundational step for women over 35 who are trying to conceive.

Antioxidants and reducing oxidative stress

Oxidative stress increases with age and is the primary driver of declining egg quality. An antioxidant-rich diet, dense in colourful vegetables, berries, extra virgin olive oil, nuts, seeds, and oily fish, directly counteracts the free radical damage that accumulates in eggs over time. Specific antioxidants that are well supported by research for this age group include vitamins C and E, selenium, zinc, alpha-lipoic acid, and N-acetylcysteine, all of which protect egg DNA and mitochondrial membranes from oxidative damage.

Vitamin D

Vitamin D deficiency is extremely common among women of reproductive age and becomes increasingly significant as a fertility factor after 35. Observational studies consistently indicate improved pregnancy and live birth rates in women with sufficient vitamin D levels, particularly in those undergoing assisted reproductive technology. This is one of the most straightforward deficiencies to identify and address, and yet it remains one of the most consistently overlooked.

Folate and methylation

Folate and its active form, methylfolate, are essential at every stage of fertility and early pregnancy. They support DNA synthesis, chromosomal stability, and the methylation processes that govern gene expression in the developing embryo. For women over 35, whose eggs are more prone to chromosomal errors, ensuring optimal folate status is not optional. Women with an MTHFR gene variant may need the active methylfolate form rather than standard folic acid, something that can be identified through functional testing.

Blood sugar, inflammation and hormonal health

Chronically elevated blood sugar and systemic inflammation both accelerate the cellular ageing process that affects egg quality. An anti-inflammatory, low-glycaemic dietary approach, rich in fibre, healthy fats, and plant-based foods, slows this process and supports the hormonal environment needed for regular ovulation and healthy implantation. These factors become increasingly important after 35, when the hormonal system has less tolerance for metabolic stress.

Starting earlier makes a meaningful difference

The most important thing you can do if you are over 35 and thinking about conceiving is to start your nutritional preparation as early as possible. The 90-day egg maturation cycle means that ideally you want to begin optimising your diet, addressing deficiencies, and implementing a targeted supplement protocol at least three months before you plan to start trying, and ideally longer.

This is not about perfection. It is about giving the eggs that matter most the best possible cellular environment in which to mature.

The bottom line

Yes, it is statistically harder to conceive after 35. But age is one variable among many, and nutrition is one of the most powerful modifiable variables available to you. You cannot increase your egg supply, but you can meaningfully influence the quality of the eggs you have. The research is clear that targeted nutritional intervention, including CoQ10, omega-3s, antioxidants, vitamin D, and folate, along with a whole-food, anti-inflammatory diet, can support egg quality, reduce chromosomal risk, and improve both natural and assisted conception outcomes for women in this age group. Starting sooner rather than later, with a personalised plan built around your specific biology and goals, gives you the best possible chance.

Sources: American Society for Reproductive Medicine guidelines; Evidence Based Birth (advanced maternal age, 2025); PubMed systematic review and meta-analysis of natural conception rates in women over 35 (2020); PMC Cell Metabolism (CoQ10 restores oocyte mitochondrial function); Frontiers in Cell and Developmental Biology 2025 (CoQ10 and female fertility); PMC (omega-3 fatty acids and egg quality); Oxford University CoQ10 research via Illume Fertility 2024; Mayo Clinic pregnancy after 35; Cofertility fertility statistics 2025; CDC National Vital Statistics 2024.