Poster 49th Nutrition Society of Australia Annual Scientific Meeting 2025

The effect of continued folic acid supplementation on post-natal depression: protocol for a randomised controlled trial.  (129546)

Olivia Gray 1 , Tim Green 2 , Luke Grzeskowiak 3 , jacqueline gould 4
  1. College of Nursing and Health Sciences, Flinders University, Adelaide, SA, Australia
  2. College of Nursing and Health Sciences, Flinders University, Adelaide, South Australia, Australia
  3. College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia
  4. Women's and Kid's Theme, South Australian Health and Medical Research Institute, Adelaide, South Australia , Australia

 

Background: Postnatal depression affects up to 20% of Australian mothers, approximately 60,000 women annually, and imposes an estimated economic burden of $877 million per year1,2. Postnatal depression is a complex and multifactorial condition, with its aetiology still not fully understood, making prevention challenging. Nutrition has been identified as a modifiable factor that may influence the risk of developing postnatal depression. A recent systematic review in non-pregnant, adult populations found folic acid supplementation was associated with reduced depression scores in individuals with clinical depression, though study quality was a limitation3. Observational studies suggest folic acid supplementation throughout pregnancy may lower the risk of postnatal depression4,5. However, no randomised controlled trials have investigated whether continuing folic acid supplementation throughout pregnancy influences postnatal depression.

Aim: To determine whether continuing folic acid supplementation throughout pregnancy, compared to ceasing after the first trimester, reduces postnatal depression risk as assessed by Edinburgh Postnatal Depression Scale (EPDS). A secondary aim is to examine whether polymorphisms in folate metabolism genes influence response to folic acid and postnatal depression risk.

Methods: This sub-study is embedded within the Folic Acid in Gestation (FIG) trial—a decentralised, double-blind, randomised controlled trial with two parallel groups. A total of 2,826 pregnant women (1,413 per group), between 12+0 and 15+6 weeks’ gestation, will be randomised to receive either a standard prenatal vitamin and mineral supplement containing either 0 µg folic acid or 500 µg folic acid. Supplementation will continue from 12+0 weeks of gestation until three months postpartum. Participants will be asked to provide a saliva sample for DNA extraction and analysis, to explore how polymorphisms in genes related to folate metabolism influence risk of postnatal depression.

Outcome: The primary outcome of this sub-study is postnatal depression, assessed using the Edinburgh Postnatal Depression Scale (EPDS). The EPDS is a validated 10-item questionnaire designed to identify symptoms and risk of depression in the postnatal period. Participants will be invited to complete the EPDS at six months postpartum. Scores of ≥13 indicate a higher risk of depression and warrant referral for clinical assessment. To account for baseline mental health status, participants will be screened for depression during pregnancy using the Centre for Epidemiologic Studies Depression Scale (CES-D) at enrolment and 28 weeks’ gestation. Based on an approximate depression rate of 20% in Australia, this sample size will allow us to detect a 25% reduction in the risk of postnatal depression. Given the burden of postnatal depression in Australia, even modest reductions in prevalence could yield significant societal and economic benefits.  

The FIG Trial is funded by the Women's and Children's Hospital Foundation. This PhD is supported by an Australian Government Research Training Program Scholarship and a National Industry PhD Scholarship. 

  1. PwC Consulting Australia (2019). Gidget Foundation Australia.
  2. Eastwood J, Phung H & Barnett B (2011) Aust N Z J Psychiatry, 45, 1040–1046.
  3. Khalili P, Asbaghi O, Aghakhani L et al. (2023) Nutr & Food Science, 53, 521–534.
  4. Yan J, Liu Y, Cao L et al. (2017) Nutrients, 9, 1206.
  5. Lewis S, Araya R, Leary S et al. (2012) Eur J Clin Nutr 66, 97–103.