VEGETARIAN & VEGAN PREGNANCY

Midwifery care involves discussion about healthy nutrition during pregnancy and breastfeeding. With the number of people moving to more plant-based nutrition on the rise, this article takes a look at the latest information and resources to support midwifery care for those who follow a vegetarian or vegan diet.

THE RISE IN PLANT-BASED EATING

According to a recent Colmar-Brunton poll, a third of all Kiwis now eat no meat, or are reducing meat intake. Vegan was the most googled diet in Aotearoa in 2019, and demand in supermarkets for plant-based food options has increased by 36% (Stuff, 2019).

The Auckland region boasts the highest vegan population in the country, and Wellington is home to the highest percentage of vegetarians. Northland and Waikato have the highest proportion of meat-reducers. Globally, there is a higher percentage of vegetarianism in the younger population and in people of colour. The number of people adopting plant-based diets is expected to continue rising.

Importance Of Healthy Diet And Lifestyle

What we eat and how active we are plays an important part in our overall health and wellbeing.

Many factors contribute to people’s food and physical activity choices, and ultimately their health.

These include social, cultural, economic, practical and personal factors and it is important to acknowledge that many are outside people’s direct control.

Differences in these underlying factors contribute significantly to inequities related to diet, physical activity and health in Aotearoa.

Healthy eating patterns are particularly important before conception, during pregnancy and while breastfeeding, because pregnant and breastfeeding women require extra nutrients. Healthy eating patterns can lower the risk of hypertensive disorders of pregnancy and gestational diabetes, as well as improve birth outcomes (USDA, 2019) and the long-term health of the baby (Horta and Victora 2013; Horta et al 2015; Koletzko et al 2019).

He Korowai Oranga (the Ministry of Health’s Māori Health Strategy) incorporates the concept of pae ora - healthy futures for Māori, as its overall aim. Pae ora is a holistic concept that includes three interconnected elements – mauri ora (healthy individuals), whānau ora (healthy families) and wai ora (healthy environments). Pae ora is a tool to help health practitioners think beyond narrow definitions of health, to consider the individual, the whānau, and the environment. As such, it is a useful model to draw on when considering the wider determinants of health and wellbeing. Mauri ora focuses on providing the individual with what they need to live with good health. Whānau ora considers the wider family group and acknowledges that for many Māori, whānau is the principal source of strength, support, security and identity. Wai ora acknowledges the importance of Māori connections to whenua as part of the environments in which we live and belong – and the

Did you know?

The World Health Organisation has classed processed meat (bacon, ham, salami etc) as a group 1 carcinogen, the same category as cigarettes, alcohol and asbestos (WHO, 2015).

Plant based diets are associated with an overall lower incidence of colorectal cancer, prostate cancer, and postmenopausal breast cancer (Orlich, M.J., et al (2015); Loeb, S., et al (2022); Watling, C.Z. et al (2022)).

82% of starving children live in countries where plant-based food is fed to animals, and the animals are eaten by people living in wealthy countries (University of Colorado, 2022).

Animal agriculture’s detrimental environmental impacts include animal gas emissions, nitrous oxide from animal waste, deforestation for farmland and stock feed. Nearly half of New Zealand’s greenhouse gas emissions are from agriculture (Ministry for the Environment, 2022).

significant impact this has on the health and wellbeing of individuals, whānau, hapū, iwi, and Māori communities.

Globally, people are increasingly focusing on the way food is produced and consumed, and the negative impacts intensive animal agriculture is having on the environment. With some additional attention to certain nutrients (such as iron, B12, calcium, and Vit D) vegetarian and vegan diets can be a healthy option during pregnancy.

WHAT IS A ‘PLANT-BASED’ DIET?

It may seem that there is a never-ending list of terms to describe various plant-based diets, however these can primarily be summarised into two main categories.

Vegetarian diets typically comprise of plant foods such as grains, legumes, nuts, seeds, vegetables, and fruit, and exclude all kinds of animal food including meat (pork, beef, mutton, lamb, poultry, game, and fowl), meat products (sausages, salami, and pâté), fish, molluscs, and crustaceans.

A standard vegetarian diet is often referred to as lacto-ovo-vegetarianism and includes dairy products, eggs, and honey, together with a wide variety of plant foods. Subcategories are lacto-vegetarianism (excludes eggs), ovo-vegetarianism (excludes dairy products but includes eggs) and pescovegetarianism (includes consumption of fish).

Vegan diets include the same wide variety of plant foods and exclude meat, dairy products, eggs, honey, and any other food derived from animals (i.e. gelatine).

‘Flexitarians’ generally eat a mostly plantbased diet, but occasionally eat meat.

REASONS FOR GOING MEAT-FREE

The most common reasons for adopting a plant-based diet include health benefits, environmental consciousness, animal welfare concerns, religion/spirituality, and cost. Health is the strongest motivator for older people to adopt a plant-based diet and environmental impact is top of mind for the younger generation (Sebastiani et al, 2019).

PLANT-BASED DIET IN PREGNANCY

Current evidence highlights that wellbalanced vegetarian and vegan diets should be considered safe for the mother’s health and for babies during pregnancy and lactation (Sebastiani et al, 2019). Whilst it is important to monitor for nutritional deficiencies during a vegan or vegetarian pregnancy, if an adequate intake of nutrients is maintained, pregnancy outcomes are similar to those reported in the general population. Exclusively plant-based nutrition during pregnancy is not associated with pre-term birth or fetal growth restriction, and there are data demonstrating a protective effect of plant-based nutrition on anthropometric fetal development (explained by the high content of vitamins in such diets). A plant-based diet may also be protective against development of gestational diabetes (Sebastiani et al, 2019). Some nutritional requirements will increase as pregnancy progresses.

Moh Eating And Activity Guidelines 2020

In November 2020, the Ministry of Health published an updated version of Eating and Activity Guidelines for New Zealand Adults (MoH 2020). The guidelines provide evidence-based recommendations on healthy eating and physical activity for all New Zealand adults (including recommendations and information for pregnant and breastfeeding women) and represent a shift away from meat-focused diets.

The Eating and Activity Guidelines (MoH 2020) describe an eating pattern that is largely plant-based, and allows for moderate amounts of animal-based foods (eggs, dairy, poultry, seafood) and small amounts of red meat. The guidelines recommend:

• Exclusive breastfeeding until six months of age, and continued breastfeeding until two years and beyond

• Eating ‘whole and less processed’ nutrientdense foods

• Limiting highly processed foods with saturated fats, added sugar and salt

• Not overeating, and balancing intake with activity to achieve and maintain a healthy weight

• Choosing, preparing, cooking and storing food in a way that optimises food safety and minimises wastage

• Allowing for cultural preferences and different eating patterns, including those ranging from totally plant-based to a mixed intake of animal and plant-based foods. The Ministry guidelines state that other than the supplements which are universally recommended pre-conceptually, in pregnancy and post-partum, most people do not need to take additional dietary supplements. The only supplementations recommended by the Ministry are:

Universal supplements (for every women pre-conceptually, during pregnancy and breastfeeding):

• Folic acid from at least four weeks before pregnancy and throughout the first trimester (800 mcg/day for most women, 5mg/day for those at increased risk of NTD, and those taking anti-epileptic medications or insulin)

• Iodine 150mcg/day during pregnancy and breastfeeding

Additional targeted supplements (for those who require them):

• Vitamin D for those at risk of deficiency (guideline currently under review)

• Iron for those with iron deficiency anaemia

• B12 supplementation for those following a vegan diet

New Vegan Pregnancy Resource

The Vegan Society of Aotearoa New Zealand have just published a new resource to help guide healthy eating during pregnancy. The Vegan Pregnancy resource (above) is informed by the Ministry of Health Eating and Activity Guidelines (2020), and aligns closely with those recommendations.

The College encourages midwives to use the Vegan Pregnancy resource and refer to the Vegan Society website, which provides further information about plant-based diets, including recipes and other resources.

Specific Nutrient Considerations

When supporting vegan whānau during hapūtanga, it is important to provide information and support, to ensure they are meeting their protein, iron, vitamin B12, vitamin D, and calcium requirements. Including iron-fortified foods and plantbased milk alternatives fortified with vitamin B12, vitamin D and calcium (ideally soy milk, as it is higher in energy and protein) can help to boost nutritional intake. Most commercial plant-based milk alternatives are fortified with calcium, but only some are fortified with vitamin B12. Some plant-based milk alternatives may be low in protein and contain added sugar, so check the ingredients list and the nutrition information panel. Manatū Hauora recommends soy milk rather than rice, oat or nut milk because it is higher in protein than these other milk alternatives.

Eating plenty of vegetables during pregnancy and when breastfeeding helps to provide important nutrients like folate, as well as vitamin C, which helps in absorbing iron. It can also help to establish healthy taste preferences in the infant. When a woman eats bitter vegetables (e.g. broccoli, rocket, watercress, pūhā, and taro leaf) during pregnancy and while breastfeeding, it can improve a child’s acceptance of vegetables in early childhood (Gerritsen and Wall 2017).

Vitamin C is found in a range of fruits and vegetables (e.g. kiwifruit, oranges, broccoli, red capsicum, berries, kūmara, tomato and silverbeet) and can help the body to absorb non-haem iron found in plant-based foods when eaten at the same time. This is especially important for vegetarian and vegan mothers.

Iron

The demand for iron during pregnancy is greater, to compensate for a higher maternal blood volume and support healthy fetal development. Iron requirements increase as pregnancy progresses and iron deficiency is common during pregnancy, causing symptoms such as fatigue, poor concentration and increased risk of infection. Anaemia increases the risk of symptomatic PPH, infection, mortality, and cardiovascular stress (Scholl & Reilly 2000).

Severe maternal iron deficiency can result in a sub-optimal iron supply to the baby, with associated increased risks of perinatal mortality, pre-term birth, and lower birthweight (Scholl & Reilly 2000). Maternal iron deficiency in pregnancy can lead to longterm consequences for the baby, including effects on cognition, behaviour, motor development, activity and physical capacity, and may not be reversible. Iron deficiency during breastfeeding leads to increased risk of maternal illness, tiredness and breast infection. For a comprehensive overview of anaemia in pregnancy, see the June 2021 issue of Midwife.

The recommended daily intake (RDI) of iron for pregnant women aged 14–50 years is 27mg per day. About 40 percent of women aged 15–44 years in New Zealand have an inadequate intake of iron and the highest prevalence of low iron stores, iron deficiency and iron-deficiency anaemia is among Māori women (especially those aged 15–24) (Russell et al 1999; Ministry of Health 2020).

The main sources of iron for women aged 25–44 years in the New Zealand diet are bread (13%), red meat (11%), breakfast cereals (9%), and vegetables (8%) (Russell et al 1999). VITAMIN

Vitamin B12 is essential for normal blood and nerve function in the body. Pregnant women need enough B12 to

Did you know?

The PREFORM study in Toronto (2016) found prevalence of B12 deficiency in pregnancy to be 17% in the second trimester and 38% at full term (across the whole pregnant population).

Metformin (an antihyperglycemic agent used as first-line treatment for prediabetes and diabetes) may reduce the absorption of vitamin B12 and significantly reduce serum vitamin B12 concentrations.

meet their own needs and to ensure healthy fetal development. Low maternal serum concentration of B12 during the first trimester is a risk factor for neural tube defect and poor maternal outcomes such as pre-eclampsia, macrocytic anaemia, and neurological impairment. Evidence is now emerging that there is a strong association between maternal B12 deficiency during the third trimester and infant deficiency at birth. Infant tolerance to deficiency of vitamin B12 is much lower than adult tolerance and breastfed infants may suffer serious consequences even if their mothers are not showing clinical signs of deficiency. There are some recent reports from European newborn screening programmes who have recently begun looking for vitamin B12 deficiency on heel prick cards, and found that it is unexpectedly common. Maternal serum B12 levels of <394 pmol/L at 18/40 are a powerful predictor of B12 deficiency in infants.

Breastfeeding women are also providing a supply of B12 for their babies via breast milk.

As B12 is primarily found in animal foods and fortified foods, pregnant or breastfeeding women who follow a vegan diet will likely require B12 supplementation even if they are showing no signs of deficiency. If women have received treatment for B12 deficiency during the pregnancy, B12 levels should be reassessed two months post-partum to confirm whether levels have returned to normal.

The RDI of B12 for pregnant women aged 14–50 years is 2.6mcg per day. The RDI for breastfeeding women aged 14–50 years is 2.8mcg per day.

Vitamin B12 is synthesised by bacteria and found primarily in animal products (e.g. meat, eggs, milk and milk products).

Plant sources (such as nori seaweed) often contain vitamin B12 analogues, which have not been shown to have vitamin B12

Screening during pregnancy for vegetarians and vegans

First antenatal blood tests

Ideally undertaken in the first trimester of pregnancy (or pre-conception), screen for iron and B12 deficiency by including:

• Routine 1st antenatal bloods

• Ferritin (+ CRP)

• B12

• Folate

Subsequent antenatal blood tests

At 28/40, include:

• CBC and antibody screen

• Ferritin (+CRP)

• B12

• Folate

Postnatal blood tests activity in the human body. Bacteria in the human intestine synthesise B12, but the bio-availability of this B12 is uncertain (Martens et al 2002). The main dietary sources of vitamin B12 for New Zealand women aged 35–44 years are milk (18%), red meat (17%), seafood (16%), and egg dishes (6%) (LINZ Research Unit 1999). For vegetarians, milk and milk products are a potential source of vitamin B12. The only dietary sources for vegans are plant foods exposed to vitamin B12 producing bacteria; plant foods contaminated with soil, insects or other substances containing B12; or foods fortified with vitamin B12 (such as nutritional yeast, soy milk, and textured vegetable protein (TVP)). Vegans often need to take vitamin B12 supplements or eat foods that have been fortified with vitamin B12 during pregnancy.

For those who have had deficiencies during pregnancy, re-check levels 4-8 weeks postpartum to allow for discussion and ongoing treatment planning. Some may require follow-up tests if deficiencies persist.

Calcium

Calcium is required for the normal development and maintenance of the skeleton. It is present in the bones and teeth to provide structure and strength. Calcium status is affected by vitamin D status, so it’s important to consider possible vitamin D deficiency as well. Fetal requirements for calcium during pregnancy are significant but can be met by increased maternal calcium absorption, turnover and retention in early pregnancy. Most of the calcium required by the baby is transferred during the third trimester (Institute of Medicine, 1997).

Calcium supplementation during pregnancy is not generally necessary, however is recommended for women with inadequate dietary intake or at risk of developing hypertensive disorders of pregnancy. A vegan diet is likely to be low in calcium, so supplementation is recommended.

The recommended daily intake (RDI) for pregnant and breastfeeding women aged 19 years and over is 1,000mg per day, and the RDI for pregnant and breastfeeding women aged 14–18 years is 1,300mg per day. Adolescent pregnant and breastfeeding women have an increased requirement because their own bones are still growing (NHMRC, 2006).

The principal dietary sources of calcium for New Zealand women aged 25-44 years are milk (38%), cheese (11%), bread (6%), non-alcoholic beverages (6%), dairy products (5%), and vegetables (5%) (Russell et al., 1999). Foods vary greatly in their calcium content; milk has a particularly high calcium content, but other excellent sources include cheeses, yoghurt and calcium-fortified soy beverages. Other good sources include nuts, canned fish with bones, green leafy vegetables and dried fruit (Goulding, 2002).

Vitamin D

Vitamin D deficiency during pregnancy may increase the risk of pre-eclampsia, gestational diabetes, fetal growth restriction, pre-term birth and hypocalcaemia. In infants, it is related to an inadequate immune system, eczema, wheezing, and respiratory infections.

In Aotearoa it is difficult to achieve an adequate intake of vitamin D through diet alone, as only a few foods contain vitamin D or are fortified with it. The primary dietary sources are seafood, dairy products, eggs, and fortified foods, therefore a vegan diet may require extra supplementation. Further information on risk based screening can be found on the Manatū Hauora (MoH) website. square

References available on request.