Ten useful things to know when consulting with larger-bodied breastfeeding or lactating women

1. 50% of Australian mothers entering pregnancy are affected by overweight or obesity.

2. Genetic contribution to adult BMI is 40-70% - obesity is polygenetic.

3. One biological parent with obesity increases a woman's risk of developing obesity three to four times; two parents increases risk tenfold.

4. Diets only work in the short term.

5. We need to address weight stigma with respect and careful use of language e.g. "living with obesity", "larger-bodied woman", "movement" (instead of exercise), "low-inflammatory diet patterns" and "reduced processed foods" (instead of talk of calories and portion sizes), person-centred languages.

6. Breastfeeding protects children against overweight and obesity in later life.

7. Maternal obesity is associated with earlier weaning, for complex reasons which may relate to the known increased risk for obese women of

   • Delayed onset of lactation

   • Infant supplementation with formula.

8. Poorer breastfeeding outcomes could also be explained by

   • Fit and hold challenges (typically not prioritised or well managed within health systems currently)

   • Blunted prolactin response to suckling? - unlikely since prolactin doesn't drive galactopoiesis

   • Insulin resistance which affects insulin-sensitive key pathways of gene expression in the lactocyte

   • Pro-inflammatory state of obesity which may impair substrate availbility for milk secretion

   • Higher rates of obstetric and delivery complications (C-sections, NICU)

   • Allostatic load of weight stigma: psychosocial burden.

9. If the woman is post-bariatric surgery and especially if post gastric by-pass, B12 and B12 supplementation requiers monitoring.

10. Semaglutide has not been detected in breastmilk samples, and findings support the conclusion that direct infant risk due to semaglutide in milk is negligible.

    • Semaglutide reduces food intake. The lactating woman needs calories to make milk.

    • Avoid semaglutide use in the early postpartum.