Blog Post

Improving Fertility in Females: A Dietitians Guide

Woman Holding Pregnancy Test

Have you and your partner made the momentous decision to conceive? Or are you simply trying to optimise your fertility status in preparation for the future? Well, you have come to the right place. 

Nutrition plays a vital role in an individual’s fertility status. It influences the likelihood of falling pregnant. It also plays a role in the development of the child, both as a new born and in years to come.

Understandably, this places a significant amount of pressure on those trying to conceive. I encourage you to take a deep breath. The following will guide you through the top 10 tips to improve fertility in woman

  1. Blood Work

Firstly, before entering the supermarkets and purchasing every supplement under the sun we encourage getting preconception blood work done. Ask your general practitioner to test: 

Thyroid, Vit D, Iron, Vit B12, Folate, zinc and anything else that may be specific to you or your family history.

Understanding where your blood markers are at now, will facilitate the next step in optimising both diet and supplementary intake. The following will briefly explain the importance of each of these nutrients:  

Folate (Vit B9) – Folate requirements increase to 400mcg pre-pregnancy. It is required for the development of neural tube pathways and prevention of congenital abnormalities. Research shows that those who used higher amounts (above 760mcg/day) had a lower risk of spontaneous abortion. 

Food sources include:

  • Dark Leafy green
  • Beans & Legumes
  • Nuts & Seeds

Zinc – Zinc can decrease the time that a female requires to fall pregnant. It also improves the quality and maturation of the egg.

It is important to have good levels of zinc prior to falling pregnant. Its primary transport occurs during the first stages of pre-implantation.  Requirements are 8mg in woman and 11mg in pregnant woman. 

Zinc is typically found in protein rich foods:

  • Oysters
  • Beef & chicken
  • Eggs
  • Legumes

Vitamin D – Even though we live in Australia, 25% of us are deficient. Vitamin D has some of the strongest evidence behind it. Those with optimal levels of Vit D (100-150mmol) have increased chances of fertility, healthy pregnancy, live birth and breastfeeding outcomes. It’s a nutrient that’s hard to get through diet, therefore supplementation may be required. 

  • Eggs 
  • Salmon & tuna
  • Mushrooms in the sun

Vitamin B12 – Brain and nervous system function, important in folate methylation cycle. Requirements are 2.4ug/day for women, which increases to 2.6ug/day for pregnant women. Supplement is necessary for vegetarians and vegans. Vitamin B12 is found in:

  • Animal products
  • Soy milk
  • Nutritional yeast

Iron – Is essential for transporting oxygen around the body, 20% of women are deficient. Iron requirements increase from 18mg per day in menstruating women to 27mg per day in pregnant women. A study showed that women who take an iron supplement are more likely to conceive faster. Iron-rich foods include: 

  • Red meat
  • Fish
  • Chicken
  • Fortified grains
  • Tofu

I’ll explain this shortly, but red meat also has a high amount of saturated fat. This should be moderated when trying to improve fertility. 

Long-chain Omega 3 – Can enhance female fertility and egg health. Women who consumed 8 or more serves of seafood per menstrual cycle had 61% greater fecundity (ability to produce offspring). DHA and EPA are the active forms of omega 3. They can be found in:

  • Marine fish (salmon, sardines, maceral, tuna or trout) 
  • Eat fish/seafood 3x per week – this is good for both males and females.

Choline – Significant role in the nervous system and developing a healthy placenta. Not essential, but our body doesn’t make enough for pregnancy. Less than 1% of people get enough Choline every day. Choline is not included in many prenatal supplements, so we encourage increased intake in:

  • Eggs 
  • Beef
  • Brussel sprouts
  • Potatoes 
Blood Test

2. Copious Amounts of Colours

Antioxidants are molecules that slow the damage to healthy cells inside of the body. Currently, there is low-quality evidence to show that high antioxidant intake may benefit subfertile women. They are abundant in dark leafy greens, beetroots and berries and other vibrant fruits and vegetables.

Furthermore, these fruits and vegetables contain high amounts of fibre which is linked to improved fecundability. The research shows that those who consume higher amounts of complex carbohydrates have decreased inflammation and better blood glucose control. Both are associated with improved fertility. Example foods include: 

  • Wholegrains, brown pasta and rice
  • Beans and legumes 
  • Potato and sweet potato
  • Fruit and vegetables

The Fibre RDI is 25g/day for women, this increases to 28g/day for pregnant women and 30g/day for lactating women. Though this is the recommended amount, health outcomes improve as fibre consumption increases. Especially for those managing a chronic disease or weight. 

Colourful fruits and vegetables

3. Reduce Sugar Intake 

A study consisting of 18,555 women showed that 90% had an increased risk of infertility when consuming a diet high in glycaemic load. A high intake of sugar was associated with an increased risk of insulin resistance and dyslipidaemia; both precursors for ovulatory disorders. Interestingly, standard soft drinks have also been identified as the main risk of ovulatory infertility. 

The World Health Organisation recommends limiting added sugar to less than 25g or 6tsp per day. 

Some strategies to reduce sugar intake include:

  • SWAP sugar for artificial or natural sweeteners where possible
  • OPT for fruit over sweets when craving something sweet
  • MODERATE sugar intake. Our taste buds adapt. Gradually reducing sugar by ½ tsp per day could accustom your taste buds. 

4. Reduce Saturated Fat Intake

The evidence is also pretty clear regarding female fertility and saturated fat intake. Those who consume a high amount of saturated fat typically have a lower number of healthy eggs produced. Same for those with an imbalanced ratio of saturated fat to polyunsaturated fats. 

This could be related to the saturated fat causing insulin resistance, inflammation or increased subcutaneous fat. 

It’s recommended that we consume <10% of our daily intake coming from saturated fats. 

For example, if your energy requirement was 2000cal/day, that would equate to <13g saturated fat per day. In saying that, the lower the better. 

Saturated fats come from: 

  • Animal Fat
  • Dairy Products
  • Processed food such as cakes, biscuits, chips, sausages, pies and pastries
  • Deep fried food
  • Coconut and palm oil
Good fats vs bad fats

5. Reduce Endocrine Exposure

Increased use of manmade plastics not only affects the environment but also female and male fertility. Endocrine-disrupting chemicals (EDC), namely BPA, PCBs, and organochloride pesticides have been negatively associated with female fertility and fecundity. This is due to their interference with oestrogen, androgen and thyroid hormone signalling pathways. 

It’s recommended to swap plastics for stainless steel, ceramic or glass.

6. Manage Alcohol and Caffeine Consumption

Enjoy a glass of wine each night or a hot cup of coffee in the morning? This may not be the worst thing in the world. 

Beverage consumption is one of the most researched areas in female fertility. Though the results are mixed, they currently lean towards improving fertility in women. This is may be due to a few reasons:

  • Caffeine and alcohol intake both improve insulin sensitivity, which we confidently know improves fertility in women. 
  • Neither of these nutrients affects the biological markers of ovarian aging.   

In saying this, no “safe amount” of alcohol has been identified in the research. A 2016 study found that up to 14 standards of beer or wine did not affect fertility in women. 

Fom another perspective, research indicates that alcohol affects the foetus as early as the first stage of implantation. So, this obviously needs to be a consideration too if trying to conceive. 

Caffeine intake from sugar-free beverages such as coffee and tea currently shows no strong correlation with fertility in women. Once again, no “safe doses” have been established so it’s still recommended to moderate consumption <2 caffeinated beverages per day. 

Alcohol intake reduces conception rates

7. Manage Pre-Existing Conditions

The majority of females encounter some form of ovulatory dysfunction, including:

They each require their own in-depth explanation (see the links) on how to best manage them. If you have any of these conditions, managing this will most likely move the needle the most in your fertility journey. 

The reason being is women with lower body fat percentages (<15%) often experience irregular menstrual cycles and decreased sex drive. When the body is deprived of energy, it starts to downregulate reproductive function. This is to preserve energy for more vital systems.

PCOS Infographic

8. Weight Reduction

Women in larger bodies may struggle to fall pregnant. There are definitely ways to improve fertility irrespective of weight, as mentioned in the above dot points. If you’re of a higher body fat percentage, a reduction of 5-10% body weight may be beneficial.

Higher body fat percentages have been associated with:

  • Impaired ovarian development
  • Decreased quality and quantity of eggs
  • Fertilisation
  • Embryo development
  • Implantation.

The probability of falling pregnant decreases by 5% every 1 point over BMI 29. In addition, BMI over 25 correlated with neural tube defects and over 30 is associated with increased risk of miscarriage.

If you’re considering this pathway, we recommend you take 6-12 months to pursue weight loss before actively trying to conceive. Working with a team of health care professionals can be beneficial to get the support you deserve during this process. 

Fertility Hormones

9. Commence Supplementation

If you are trying to conceive, we recommend commencing prenatal supplements 3 months in advance. This will optimise your nutrition status to ensure bub is conceived with a nutrient-rich egg.

Unfortunately, there is no one size fits all supplement. Working closely with a doctor or dietitian assist you to find what is most suitable for you. Factors to consider:

  • Dietary Patterns – Many supplements contain animal products, which is important to consider for vegans and vegetarians. 
  • Weight – E.g. Those who have a BMI >30kg/cm2 require additional iodine supplementation
  • Currently pregnant – Each trimester will influence your nutritional requirements

Any of our dietitians at Ideal Nutrition can support you in finding a supplement that’s tailored to you. 

10. Manage Mental Health

What came first? The chicken or the egg? Being deemed as sub-fertile can place immense stress on a couple which can decrease fertility even further. 

In Australia, one in five women experiences depression and one in three women experience anxiety at some point in their life. We know that any form of physical stress can result in irregular menstrual cycles. The literature also shows that those who undergo cognitive behavioural therapy all have increased rates of falling pregnant. Other options such as mind-body therapy, psychotherapy or anti-depressants also help.

Furthermore, those who are pursuing the assisted reproductive technology route should especially consider cognitive therapy. This can help overcome feelings of depression or anxiety. It has been identified that the cortisol hormone released when an individual is stressed can play a role.

Mental health strategies:

  • Gentle exercise
  • Meditation
  • Cognitive Behavioural Therapy 
  • Mind Body Intervention
  • Psychotherapy
Meditation in Nature

Bonus factors for Increasing fertility

  • Exercise – Moderate exercise can improve ovulation and fertility in women, especially those who are obese or require IVF. Just make sure it’s moderate (3-4 sessions/week). Excessive exercise can have the opposite effect.
  • Stay hydrated – ensure that your urine is a pale to clear yellow. Cervical mucus and sperm are made from water, so it’s important that we’re consistently hydrated.
By Hanah Mills

Hanah is an outgoing Dietitian, with a keen interest in sports dietetics. Her background in Crossfit and weightlifting has led her to understand the crucial role that nutrition plays in enhancing athletic performance. Hanah graduated from Griffith University with a Bachelor of Nutrition and Dietetics. She is also undergoing further studies to become an accredited sports dietitian. She believes in the importance of getting to know each person and applying appropriate interventions to support their individual goals and lifestyle.