Why is pre-conception nutrition important?

December 12, 2021
Written by Sara Alcala
Fertility & prenatal dietitian- Dedicated to empowering women to optimize their nutrition and lifestyle to take control of their fertility journey.
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It is commonly well-known how important it is to eat well during pregnancy. Everyone knows that when you are pregnant, nutrition is more important than ever!! You have been told that you need more of many important nutrients than you did before pregnancy.
Easily you become more aware of how your food choice every day will help you give your baby what he or she needs to develop, and that’s great!!!! But what about before you fall pregnant?

With about 50% of pregnancies being unplanned, it is helpful to work on developing good habits in an earlier stage, to not only boost your fertility, but it can also even have a lifelong impact on your baby’s health and the rapid increase in the prevalence of metabolic, allergies and chronic diseases too!

A growing body of evidence shows that the first one thousand days of a baby’s life provides a critical window of opportunity where a healthy environment, in particular, diet and lifestyle can positively impact and influence lifelong health. You have heard well?

During both periods, before conception and during pregnancy exposure to environmental factors can trigger adaptations in the growing fetus. While these effects may be adaptive in the short term, they may also be associated with adverse outcomes in childhood and later life (such as the major risk of obesity, type 2 diabetes, heart disease, and allergy). That’s why is very important for health professionals and parents to intervene in this earlier stage (ELN) to optimize future health outcomes

In this blog, I will cover the significant role of nutrition and the environment on your future baby’s genetics, the importance of maintaining a healthy weight before conceiving, and how nutrition and lifestyle interventions before pregnancy can improve maternal and your future baby’s long-term health outcomes.

Furthermore, pre-conception nutrition and lifestyle may be important determinants of pregnancy outcomes and the longer-term health of the offspring. Yes, you have read this well!! Pre-conception nutrition and lifestyle have the power to not only affect your pregnancy and your baby but also your grandchildren’s health! That’s why is very important for health professionals and parents to intervene in this earlier stage to optimize future health outcomes! I know it is a big responsibility!! You haven’t thought about that before, ah? But don’t worry, I’ve got you!

What is Early Life Nutrition (ELN)?

ELN is the period from pre-conception through to toddlerhood, also known as the ‘first 1,000 days. Traditionally refers to 270 days of pregnancy (9 months), plus the first 2 years of a child’s life (730 days). However, recent research also shows that the health and lifestyle of the mother and the father during the 6 months (180 days) before conceiving a baby is essential (after all, the egg and sperm will provide the genetic material for the developing fetus), leaving it actually up 1180 days.

What is the pre-conception period?

The pre-conception period is the 3 to 12 months before conception.
This preconception period is often defined as the 3 months before conception, possibly because this is the average time to conception for fertile couples. However, a period before conception can only be identified after a woman has become pregnant.

A clear definition of the attributes of the preconception population is currently lacking. Some definitions avoid this problem, for instance, “a minimum of one year before the initiation of any unprotected sexual intercourse that could possibly result in pregnancy”.

3 months before conceiving is a critical time as eggs cells are developing and maturing before you ovulate (meiosis, which is the process where the egg follicles develop into mature oocytes ready for ovulation, takes approximately 3 months). The development of sperm also impacts the health of the embryo, as a full sperm cycle takes around 64 days, so from a biological perspective, there is a critical period spanning the weeks around conception when gametes mature, fertilization occurs and the developing embryo forms. These are the events most sensitive to environmental factors such as the availability of macro-and micronutrients or exposure to smoking, alcohol, drugs, or other teratogens.

So yes, what you eat (future mum & dad to be) now will affect your egg and sperm production in 3 months period therefore potentially the health of your future baby! Don’t leave it until you’re pregnant to focus on what you are eating! Start your fertility eating plan now!! Ideally you want to be eating well for at least 3 months prior to conception.

Besides the lack of a clear definition of the period time of the preconception from science-based evidence I totally recommend that 6-12 months is ideal to help correct any nutritional deficiencies, as well as to optimize your lifestyle and weight for conception and pregnancy. I encourage you to speak to your GP to organize a blood test to check out your current nutritional status before trying to conceive and consult with your nutritionist or dietitian to help get you on the right track.

How genetics and environment can affect your baby’s health:

Epigenetics is defined as ‘ changes in gene function that do not involve changes in the DNA sequence’ or essentially how a fetus’s environment (including nutrition) can impact the expression of a particular gene in the future.

Epigenetics is everywhere, what you eat, where you live, who you interact with, when you sleep, how you exercise, even aging- all of these can eventually cause chemical modifications around the genes that will turn those genes on or off over time.

I like to use the following analogy to explain how epigenetics work:
‘epigenetics doesn’t change the book but it does change the way that the book is read’.
It describes the heritable change in organisms caused by modification of gene expression rather than alteration of the genetic code itself.

There is some research to show we now have the potential to modify which diseases can be avoided through gene expression, by switching particular genes on and off throughout a process called methylation and histone modification.
Process of methylation- adds “tags” to human DNA that influence whether a gene is a gen turned on or off.

Histone modifications affect how tightly the DNA is wrapped around histones (when histones are tightly wound, genes may not be accessible for activation).

As mentioned Epigenetic changes DO NOT ALTER the DNA sequence but are heritable. At conception, most epigenetic information is ‘wiped’ from the genome however some of these changes remain and are inherited, even across generations. So, if the wrong genes are switched on, when they are not meant to, then it can impact the health of your baby and even your baby’s baby. Mind-blowing, right?

The way you nourish yourself before and during pregnancy quite literally shapes your baby’s health, and not just in early infancy, but for the rest of his or her life.

Nutrition is one of the most easily modifiable environmental factors during early life. It has been shown to influence both fetal and postnatal growth and development, and the risk of metabolic and allergic disease in childhood and adult life.

A study in rats indicated that nutrient-poor diets during the development of the fetus can lead to the switching on of stress pathway that increases the chance of obesity in the rat’s babies (Ruijun et al., 2012).
Men are not less, remember, sperm carries 50% of your baby’s genetic material. Several recent studies have identified links between paternal nutrition, sperm quality, and reproductive outcomes in humans. Although human studies linking environmental effects and epigenetic alterations are limited and inherently challenging, many models using mice have been studied and shed light on the importance of understanding the role of environmental factors on the father and future generations.

One study has shown that a male’s preconception health plays a part in epigenetics (Day et al., 2016). Research (mostly in animals) has shown that paternal alcohol consumption has epigenetic effects on sperm DNA, suggesting a role in the development of congenital disorders in offspring and a higher prevalence of low birth weights (Day et al., 2016). The exact amount which may be implicated is not well understood yet, it is recommended though that you do not exceed about 2 standard drinks per day for men, and aim for at least two alcohol-free days per week.

However, keep in mind that much more future research is needed in this space to further understand epigenetics in humans.

How does your weight affect your fertility?

Both maternal underweight and overweight are associated with substantial risk for maternal and child health. Therefore, maintaining a healthy weight in the 12 months leading up to conception reduces the likelihood of your child being outside of their healthy weight range later in life. Emerging research has indicated that a high woman’s BMI (body mass index) at the start of pregnancy is a strong predictor of her offspring’s risk for obesity in adult life (Davies et al., 2016).

In addition, it is also known that being above a healthy weight before pregnancy can impact your fertility and the health of your eggs (human oocyte). One study (Ruebel, L.M. et al., 2020) Found that overweight women undergoing fertility treatment had abnormal levels of fat and inflammation in the fluid surrounding their eggs, therefore they had ‘disorganized’ DNA.

Likewise, being outside of your healthy weight range at the start of pregnancy has associated with a greater risk of developing gestational diabetes, which in turn enhances your baby’s risk of developing diabetes themselves.

Hey!! It is not all bad news, I know all of this can be very overwhelming! But you can make a difference to your own and your baby’s health just by making small but very effective lifestyle and nutrition changes.

A pre-conception weight loss of 10% was shown to be associated with clinically meaningful risk reduction in pregnancy-related conditions including pre-eclampsia, gestational diabetes, preterm delivery, macrosomia, and stillbirth (Laura et al., 2015) (Stephenson et al., 2018). 

I know, reading all might feels a bit nerve-racking and terrified. However, the emerging research is growingly showing us we need to bring that awareness of the importance of health before pregnancy: pregnancy planning and uptake of interventions before conception are distinct but related requirements for improving preconception health and avoid these adverse outcomes down the track.

Speak to your fertility & prenatal dietitian for tailored and personalized advice. There is no wrong time to embrace nutrition & lifestyle changes and optimize your health. If there is a moment in your life to make nutrition a priority, the moment is NOW!

Future health outcomes for your baby

Allergies, asthma & Eczema Prevention

Allergies in children are on the rise! Australia has one of the highest rates of food allergy in the world and there have been reports that more than 10% of 1-year old children have a food allergy, 1 in 9 children have asthma and 1 in 5 have eczema.

The rise in food allergy, highlight the vulnerability of the developing immune system to early environmental exposure and how ELN has a substantial impact on the developing it.

Allergies grow out of changes in the immune system. It has been shown that these alterations can be influenced by maternal nutrition. So yes!! The nutrition of mums-to-be can influence the immune development and function of your baby.

What can you do to improve immune development before conception and throughout pregnancy? Some maternal nutritional changes have been associated with altered immune programming. These includes: 

Allergy prevention strategies:

  • Consume all main allergens frequently during pregnancy and breastfeeding: eggs, cow’s milk, fish, crustaceans, peanuts, tree nuts, wheat, sesame, lupin, and soy (DO NOT TAKE it if you are allergic to them yourself, of course!).
  • Fish oil supplementation: studies have shown that increased intakes of omega-3 during pregnancy may have protective effects on childhood allergic disease (Karen et al.,2015).
  • Folic acid supplementation
  • Adequate prebiotic fiber intake: onions, garlic, cashews, peanuts, legumes & beans, and asparagus among others- the maternal gut microbial environment is an emerging protective factor for allergy in infants.
  • Probiotics for those women with a family history of allergies, asthma, or eczema.

Asthma prevention strategies:

  • Vitamin E: extra virgin olive oil and nuts
  • Adequate antioxidant content: Studies suggest that higher intakes of antioxidant-rich foods, such as fresh fruit and vegetables, herbs, and spices may reduce the risk of asthma and/or eczema in offspring.
  • No surprisingly adapting a Mediterranean dietary pattern appears to be protective against asthma.

Eczema prevention strategies:

  • Adequate vitamin D status before conception and during pregnancy. It has been reported that vitamin D insufficient during pregnancy is associated with an increased risk of eczema, asthma, and food allergy, but also increased risk of pre-eclampsia and small-for-gestational-age infants (Davies et al., 2016). Vitamin D deficiency in pregnancy had been called a potential ‘threat ‘to the child and indication of the perceived importance of vitamin D status during this time.
  • Prebiotics and probiotics: the maternal gut microbial environment is also emerging as a potential risk/protective factor for allergy in the offspring, with maternal microbial transfer to the fetus likely to begin during pregnancy. Therefore, a healthy balance of specific microorganisms in the gut is essential for healthy immune system development. As a result, the mum’s gut microbiome can have a role in eczema development in her baby. Using soluble ‘prebiotic’ fiber has been shown to have beneficial effects on both immune status and metabolic homoeostatic. Supplementing with Lactobacillus rhamnosus GG is especially important if you have a family history of eczema.

Obesity and Chronic diseases prevention

The global obesity and type 2 diabetes pandemic are often linked to lifestyle changes such as a higher calorie diet and reduced physical activity levels. However, more recent evidence demonstrates that early life nutrition (ELN) has a key role in associated risk factors such as regulating satiety, adipose tissue development, and metabolism (Mameli et al.,2016)

Both too low or too high body weight in mums have been associated with an increased risk of childhood and adult chronic diseases such as obesity, as well as heart disease, stroke, and type 2 diabetes later in life.

Studies suggest that bereaved mums (under-eating or over-exercising) or those with food deprivation during pregnancy, condition their baby to become really good at holding onto energy. The mechanism that links maternal weight during pregnancy to later disease risk in the offspring involves a range of factors. Once the child is born, they tend to consume excessive energy because their hunger (full signals) has been altered during very early life (Davides et al., 2016).

A 2009 study of 1425 mother and infant pairs investigated the association between pre-pregnancy obesity and BMI of offspring in the first four years of life (Hu et al.,2019) results highlighted that women with higher BMI before pregnancy were significantly associated with a greater risk of higher BMI and rapid weight gain in the first four years of life. In addition to this, other emerging research shows there is a correlation between pre-pregnancy BMI and infant birth weight (Lima et al., 2018)

I know that all of these may seem a bit overwhelming right now, but trust me!! With a tailored nutrition plan and expert advice, we can beat this!! Think about it, how powerful is that, now that you know that what you eat now could prevent your baby from developing diabetes or struggling with obesity, or having chronic skin rashes later in life. Wouldn’t you do whatever is in your power to give your baby the best start in life and long-life health? 

Are you planning to conceive in the next 3-12 months? Not sure what to eat? Not sure where to start? I help couples boost their fertility and give their baby’s the best start possible with the power of good food.  Get in touch for an appointment.

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  1. 就爱要

    Where there is a will, there is a way.

    • Sara Alcala

      Absolutely true!


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