Case scenario

Raquel, 26, comes into your pharmacy to fill a prescription for lamotrigine for the treatment of bipolar disorder. She picks up a bottle of folic acid 0.5 mg tablets and asks your advice, as she plans to start trying to conceive after her upcoming holiday. Raquel explains that she has not spoken to her GP or specialist about her planned pregnancy, but has an appointment scheduled next week. You recall from previous conversations that Raquel follows a vegan diet.

Introduction

Pregnancy planning and care should include dietary and nutrient considerations to ensure healthy fetal growth and development, and the health and wellbeing of the pregnant person. Food fortification (with micronutrients such as folic acid and iodine) has shown to improve nutrient intake and/or pregnancy outcomes,¹ however supplementation with certain essential nutrients is still routinely recommended during preconception and pregnancy. 

Pharmacists play an important role in providing information about dietary sources, appropriate product selection, guidance on dosing requirements, and advice on supplements and medicines that pose a risk during pregnancy.

Already read the CPD in the journal? Scroll to the bottom to SUBMIT ANSWERS.

Key nutrients

When pregnant or planning for pregnancy, certain essential nutrients should be considered.

These include:

• folic acid
• iodine
• iron
• calcium
• omega 3 fatty acids
• vitamin B₁₂
• vitamin D.

Requirements vary between individuals and are influenced by concomitant medications, comorbidities, vitamin/mineral deficiencies and risk factors.

Folic acid

Folic acid helps prevent neural tube defects (NTDs) such as spina bifida and anencephaly.^2,3 It is present in a variety of foods (e.g. green leafy vegetables, legumes) and fortified foods (e.g. wholegrain breads, breakfast cereals).⁴

To reduce the risk of NTDs, all persons planning pregnancy or who are pregnant without certain risk factors, should take 500 mcg folic acid daily (or a pregnancy multivitamin that contains at least 400 mcg folic acid daily).^4-6

Supplementation should start from at least 1 month prior to conception and continue for the first 3 months of pregnancy.^3-5

Certain risk factors require high-dose folate supplementation. The recommended dose in these cases is folic acid 5 mg daily for 3 months before conception and continued for the first 3 months of pregnancy. Risk factors include^3,5,6:

• previous pregnancy with NTD
• close family history of NTD
• diabetes
• malabsorption issues
• BMI > 30 kg/m2
• certain medicines (e.g. anti-epileptic medications, sulfasalazine).

Those with risk factors for folate deficiency – for example, diabetes, multiple pregnancy, malabsorption issues, reduced dietary intake, drugs that alter folate metabolism (e.g. sulfasalazine) or haemolytic anaemia – should have their full blood count monitored and included in prenatal screening as specific treatment may be necessary for deficiency.²

Iodine

Iodine is key for fetal brain and central nervous system development.⁵ As it can be difficult to obtain the required amount from diet alone, iodine is incorporated in most pregnancy multivitamins.⁴ A daily supplement of iodine 150 mcg is recommended when planning pregnancy, and continued during pregnancy.^5-7

Patients with pre-existing thyroid conditions should speak to their doctor before taking an iodine supplement.⁷

Iron

Iron is essential for healthy red blood cell formation, prevention of low infant birth weight, premature birth, and prevention of anaemia in the mother.⁸ Food sources include lean meat, green leafy vegetables, dried fruit and nuts.⁴

Iron requirements increase during pregnancy, and the amount obtained from the diet alone, or the small amount present in some pregnancy multivitamins, may be insufficient and further supplementation may be required.⁹

Iron studies should be routinely performed during prenatal screening to assess iron status. At least 60 mg elemental iron daily is required to treat iron deficiency if present.⁵

Calcium

Calcium is essential for healthy bone formation. Dietary sources include dairy products, broccoli, tofu and calcium-fortified cereals.⁴ In those with inadequate dietary intake (<1,000 mg daily) additional calcium of at least 1,000 mg daily is required to reduce the risk of pre-eclampsia.⁵

Omega-3 fatty acids

Omega-3 long-chain polyunsaturated fatty acids are important for brain, nerve and eye development. Dietary sources include walnuts, linseeds, chia seeds and soybean. Fish such as tuna, salmon and mackerel can be eaten 2-3 times per week, however some fish may contain high amounts of mercury and should be avoided (e.g. shark and swordfish).⁴ Omega-3 is included in some pregnancy supplements, or specific supplements are available, however fish liver oils should be avoided due to the high content of vitamin A.⁴

In those who are low in omega-3, supplementation with 800 mg DHA and 100 mg EPA daily may reduce the risk of pre-term birth.⁷

Vitamin B₁₂

Vitamin B₁₂ is vital for development of the nervous system and new tissue, and deficiency is associated with infertility and miscarriage.¹⁰ While B₁₂ deficiency is rare, even in pregnancy, it should be excluded when unexplained anaemia is present.¹⁰

Deficiency generally occurs when there is insufficient dietary intake of animal food products (e.g. in vegetarian or vegan diets). Other risk factors include conditions that give rise to malabsorption issues (e.g. previous gastric/ileac resection, coeliac disease, inflammatory bowel disease), autoimmune disorders such as Graves’ disease, use of certain medicines such as metformin, or prolonged use of proton pump inhibitors or H2-receptor antagonists.¹⁰

Routine supplementation is recommended for vegan and vegetarian patients during pregnancy, with a recommended daily intake of 2.6 mcg daily.¹⁰ If deficiency is detected, specific treatment guidelines should be followed.

Vitamin D

Vitamin D is essential for fetal bone development and maternal bone health. Vitamin D deficiency is associated with bone weakness, muscle pain, skeletal abnormalities (rickets) in the baby, and small for gestational age babies.¹¹

Risk factors for vitamin D deficiency include dark or tanned skin, lack of exposure to sunlight, and pre-pregnancy BMI ≥ 40 kg/m2. Patients with risk factors who become pregnant should have their vitamin D level checked at their first antenatal visit.¹¹

If serum vitamin D levels are found to be 30–49 nmol/L, vitamin D supplementation of 1,000 IU daily is recommended.

For a vitamin D level <30 nmol/L, 2,000 IU daily is recommended.⁵ Specific treatment guidelines should be followed. 

While vitamin D supplementation can reduce the risk of pre-eclampsia, low birth weight, and pre-term birth, the risk of pre-term birth increases when combined with calcium supplementation; medical advice should be sought in these cases.¹¹

Other important points to consider

• Supplements that are not pregnancy-specific should be avoided.⁴
• Supplements that contain high doses of vitamin A, C or E should be avoided as these can harm the unborn baby.^5,7
• While vitamin A is essential for organ development, high levels of vitamin A are known to increase the risk of birth defects and liver toxicity. Foods high in vitamin A (such as liver and liver products) and retinol-containing supplements (such as cod liver oil) are best avoided.⁴ Vitamin A supplements  should be limited to 3,000 IU per day, and all synthetic derivatives of retinol should be ceased at least 1 month prior to conception.⁵
• Pharmacists should advise that the safety and efficacy of different herbal preparations in pregnancy vary and to ensure they always check with their pharmacist before taking these.
• Pharmacists should consider the safety of other medicines when someone is planning pregnancy, or is pregnant, and refer appropriately when necessary.

Knowledge to practice 

Since pregnancy supplements are available primarily as self-selected or over-the-counter products, pharmacists play a key role in providing education and recommendations during the preconception and pregnancy stages. This includes ascertaining which concomitant medicines are being taken, which comorbidities are present, and ensuring appropriate and timely referral when risk factors for certain deficiencies are present, or when patients are taking medicines that are known teratogens. A knowledge of supplements best avoided during pregnancy is also essential.

Conclusion

The role of key nutrients is an important consideration during and when planning pregnancy. This requires the support and guidance of qualified health professionals involved in the pregnancy journey, including general practitioners, obstetricians and pharmacists, to recommend appropriate testing, monitoring, supplementation and dietary advice. Careful discernment of the variety of pregnancy supplements available is necessary to ensure adequate doses of essential nutrients are obtained with respect to the person’s individual health status, while ensuring avoidance or limitation of foods and supplements that are known to cause harm.

Key points

• Nutrient requirements should be considered for all people planning pregnancy and during pregnancy.
• Folic acid and iodine are routinely recommended preconception and in all pregnancies.
• While most other essential pregnancy nutrients are obtained through the diet, some patients require supplementation due to inadequate dietary intake or predisposing risk factors.
• Pharmacists play a key role in providing advice regarding preconception and pregnancy supplements and ensuring appropriate referral where necessary.

If you do get an enrolment error, please click here

References

1. Folic acid & iodine fortification. Australian Government – Australian Institute of Health and welfare. 2016. At: https://www.aihw.gov.au/reports/food-nutrition/folic-acid-iodine-fortification/contents/summary/outcome
2. King Edward Memorial Hospital. Folic Acid Adult Medication Monograph.2020. At: https://www.kemh.health.wa.gov.au/~/media/HSPs/NMHS/Hospitals/WNHS/Documents/Clinical-guidelines/Obs-Gyn-MPs/Folic-Acid.pdf?thn=0
3. Therapeutic Guidelines. Water Soluble Vitamin Deficiencies. 2022. At: https://tgldcdp-tg-org-au.pslibresources.health.wa.gov.au/viewTopic?etgAccess=true&guidelinePage=Gastrointestinal&topicfile=c_GIG_Gastro-oesophageal-reflux-in-adultstopic_1&guidelinename=Gastrointestinal&sectionId=c_GIG_Water-soluble-vitamin-deficiencies
4. The Royal Women’s Hospital. Food and Nutrition in Pregnancy. 2021. At:https://www.thewomens.org.au/health-information/pregnancy-and-birth/a-healthy-pregnancy/food-nutrition-in-pregnancy/
5. Dorney E, Black KI. Preconception Care. Australian Journal of General Practitioners. 2018; 47(7):424─9. At: https://www1.racgp.org.au/ajgp/2018/july/preconception-care.
6. Royal Australian and New Zealand College of Obstetricians and Gynaecologists. Pre-pregnancy Counselling. 2022. At: https://ranzcog.edu.au/wp-content/uploads/2022/05/Pre-pregnancy-Counselling-C-Obs-3a-Board-approved_March-2022.pdf
7. Australian Government – Department of Health and Aged Care. Pregnancy Care Guidelines – Summary of recommendations and practice points. At: https://www.health.gov.au/resources/pregnancy-care-guidelines/summary-of-recommendations-and-practice-points
8. Frayne J, Pinchon D. Anaemia in Pregnancy. Australian Journal of General Practice. 2019 March; 48(3): 125-9
9. The Royal Women’s Hospital. Iron in Pregnancy. 2021. At:https://thewomens.r.worldssl.net/images/uploads/fact-sheets/Iron-in-pregnancy.pdf
10. King Edward Memorial Hospital. Vitamin B₁₂ Deficiency: Management during pregnancy (Clinical Practice Guideline). 2021. At: https://www.kemh.health.wa.gov.au/~/media/HSPs/NMHS/Hospitals/WNHS/Documents/Clinical-guidelines/Obs-Gyn-Guidelines/Vitamin-B₁₂-Deficiency-Management.pdf?thn=0.
11. King Edward Memorial Hospital. Vitamin D Deficiency in Pregnancy (Clinical Practice Guideline). 2016. At: https://www.kemh.health.wa.gov.au/~/media/HSPs/NMHS/Hospitals/WNHS/Documents/Clinical-guidelines/Obs-Gyn-Guidelines/Vitamin-D-Deficiency-in-Pregnancy.pdf?thn=0#:~:text=Key%20points%20All%20women%20identified%20as%20at%20risk,The%20vitamin%20D%20level%20is

Our Authors

Kirsty Luck Bpharm is a senior hospital pharmacist who works in the North Metropolitan Mental Health Service in Western Australia. She has broad experience across various therapeutic areas within hospital pharmacy, and has previously worked in the obstetrics setting, with an interest in perinatal care.

Our reviewer

Victor Senescall (he/him) BPharm(Hon), MPS-AACPA, BArts