Improving female fertility: a dietitian’s guide
Every woman's journey to conceive (TTC) is unique and can often feel overwhelming. I hope this article provides you with a guiding hand to help you know where to begin.
Nutrition plays a vital role in both female and male fertility, influencing not only the chances of conception but also the baby’s development at birth and beyond. This highlights the considerable pressure couples face when TTC. To help ease the overwhelm, I’ve broken down the steps you can take to improve your fertility and prepare you and your body for the road ahead.
please note that this article is only covering female fertility, I have a post on male fertility coming soon
STEP ONE. Get your bloods checked
Check your current nutrition status by completing preconception blood work.
Pop in and see your GP, we want to at least test: Vitamin D, Folate (Vitamin B9), Zinc, Thyroid, Iron, Vitamin B12 + anything else that might be specific to your own medical history.
By completing your preconception bloods we have an understanding of where your blood markers are at and we can then focus on optimising both your diet and supplement requirements.
So, why do we care about these specific nutrients?
Folate (Vitamin B9) is required for the development of neural tube pathways and the prevention of congenital abnormalities. Folate requirements can vary based on your own medical history however, we generally require 400 mcg pre-pregnancy. Food sources of folate also include dark leafy greens, legumes and beans, nuts and seeds.
When it comes to zinc, zinc has been shown to decrease the time it takes for a female to fall pregnant. Zinc also improves the quality and maturation of the egg, so it’s important to have good levels of zinc prior to falling pregnant. Requirements for the general population are 8mg and 11mg for pregnant women. Food sources of zinc to include in your diet are oysters, eggs, legumes, beef and chicken.
Optimal levels of vitamin D have been shown to increase chances of fertility, a healthy pregnancy, live birth and pregnancy outcomes. Vitamin D is often hard to get through our diet alone, therefore supplementation may be needed. Some food sources to include are eggs, mushrooms (sun-exposed), salmon and tuna.
Vitamin B12 has been identified as playing an important role in brain and nervous system function, plus it has an important role in the folate methylation cycle. The requirements for women are 2.4ug/day, which increases in pregnancy to 2.6ug/day. Supplementation is often necessary for anyone following a vegan or vegetarian diet. Vitamin B12 can be found in animal products, nutritional yeast and soy products.
Iron is an essential one as it has a role in transporting oxygen around the body, iron requirement for menstruating women is 18mg, which increases to 27mg during pregnancy. Optimal iron levels are especially important prior to ttc. Dietary sources of iron include red meat, chicken, fish, tofu and fortified products.
Omega-3 has been shown to enhance female egg health and overall fertility. DHA and EPA are active forms of omega-3 and can be found in marine fish (like salmon, sardines, tuna, trout and maceral). Aim to consume fish/seafood 3x per week, and consider supplementation if you are not able to meet this.
Lastly, choline plays a significant role in the development of a healthy placenta and the nervous system of the baby. As our body is unable to make enough choline for pregnancy this is another important one to be included in our diets. Dietary choline is found in eggs, potatoes, beef and Brussels sprouts.
STEP TWO. Time to start a high-quality prenatal supplement
It's time to begin taking a prenatal supplement—if you're trying to conceive (TTC), I recommend starting at a minimum of three months in advance. This will help optimise your nutritional status, improve egg quality, and ensure your future baby is conceived with a nutrient-rich egg. Since there's no one-size-fits-all supplement, it's crucial to choose one that suits your unique needs, as individual requirements can vary greatly.
If you need help feel free to book a 1:1 consultation and we can work together to find one that best suits your needs.
STEP THREE. Optimise your diet
Let’s start optimising your diet, not only do we want to include the common nutrients we mentioned above - folate, zinc, vitamin D, vitamin B12, iron and omega-3, but we also want to optimise this.
Ensure your diet is rich in antioxidants, molecules that slow the damage to healthy cells inside the body. Including an abundance of foods like dark leafy greens, berries, beetroot and extra-virgin olive oil is a good place to start.
Include fibre in your diet through fruits and vegetables, as the research further shows that those who consume higher amounts of complex carbohydrates have better blood glucose control and decreased inflammation (both are associated with improved fertility). Include an abundance of beans and legumes, wholegrains, wholemeal or pulse pasta, brown rice, sweet potato, fruits and vegetables. The RDI for women is 25g/day (which increases to 28g/day in pregnancy and 30g/day in breastfeeding women).
Reduce your sugar intake, a high intake of sugar was associated with an increased risk of insulin resistance, and one particular study showed that 90% of women had an increased risk of infertility when consuming a diet high in glycaemic load. Start to moderate your sugar intake, it can be hard at the start but our taste buds do adapt.
Limit saturated fat intake, the research shows that those who consume a diet high in saturated fat typically have a lower number of healthy eggs. Saturated fats are linked to insulin resistance, increased subcutaneous fat and inflammation. Saturated fats come from animal products, dairy products, processed foods like cakes, biscuits, pies and pastries, deep-fried foods, coconut oil and palm oil.
Reduce alcohol and caffeine consumption, this is a well-researched area of female fertility, and the overall consensus leans towards reducing (or eliminating) intake to improve fertility. While there is no ‘safe’ or set amount to this try to limit caffeine to 1 coffee a day, and try your best to limit your alcoholic beverages.
STEP FOUR. Manage any pre-existing conditions
Manage Pre-Existing Conditions, especially those that are linked to ovulatory dysfunction such as Polycystic ovarian syndrome (PCOS), Endometriosis and Adenomyosis, Hypothalamic Amenorrhea (HA) and Related Energy Deficiency in Sports (RED-S). These will require individualised advice, so please reach out to your GP, fertility specialist or prenatal dietitian for advice.
STEP FIVE. Eliminate EDC’s
Reduce exposure to endocrine-disrupting chemicals (EDC’s). This is a BIG topic on its own and can be very overwhelming at the start. As a generalised explanation, the increased use of man-made plastics impacts female (and male) fertility, these EDCs can include BPA, PCBs, and pesticides (among many others). This is due to their interference with important hormones such as oestrogen, androgen and thyroid hormone signalling pathways. A good place to start is to swap your plastics for glass, stainless steel or ceramic and don’t heat plastics in the microwave.
STEP SIX. Track your cycle and test ovulation
If you haven't already, begin learning about your menstrual cycle and identifying when you ovulate—this is key to getting pregnant. I recommend using an app to track your cycle and noting any symptoms you experience. There are several ways to test for ovulation, with the most common methods being ovulation predictor tests (urine sticks) or basal body temperature (BBT) tracking.
FINAL POINTS.
Some final considerations.
Manage your mental health as the TTC journey and fertility struggles can place immense stress on a couple which can in turn negatively impact fertility. The statistics in Australia state that one in five women experience depression and one in three women experience anxiety at some point in their life and we know that any form of physical stress can result in irregular menstrual cycles. Research shows that those who undertake mental health support have increased rates of falling pregnant.
Implement exercise, moderate exercise can improve ovulation and fertility in women, aim for 3-4 moderate sessions/week (please note that excessive exercise can have the opposite effect).
Stay hydrated and ensure that your urine is a pale to clear yellow colour. Both cervical mucus and sperm are made from water, so consistent hydration is important.
I do acknowledge that there are ways to improve fertility irrespective of weight, however, research suggests that a modest reduction of 5-10% in body fat may be associated with improvements in fertility. While there are many ways to support fertility beyond weight management, it remains a relevant factor for your TTC journey. Higher body fat percentages have been linked to challenges such as reduced egg quality and quantity, as well as potential impacts on ovarian development, fertilisation, implantation, and embryo development. If this is a factor for you, consider allowing 6 to 12 months for a gradual and safe approach to weight management before actively trying to conceive. I highly recommend seeking personalised support to navigate this process. If you’re interested, feel free to book a session for tailored guidance.
Also, remember it takes two to make a baby, so please check in on your partner (I have an article coming soon)
This can be a very overwhelming time and you deserve support. Please feel free to reach out and book a 1:1 consultation if you would like guidance and support through this new journey.
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