The Effects of Therapeutic Ultrasound on Human Milk Composition: A Quasi-Experimental Pre-Post Design Study

Therapeutic ultrasound generates heating within tissues and is a popular treatment option for inflammatory conditions of the lactating breast, but it is unknown if therapeutic ultrasound alters breastmilk composition.

This study aimed to determine the effect of therapeutic ultrasound on the protein, lactose and fat concentrations of human milk in healthy lactating mothers.

This was a single session quasi-experimental, non-superiority, pre-post design study. Twenty-six Western Australian mothers with infants aged 1-6 months and exclusively breastfeeding were included. Mothers with inflammatory conditions of the lactating breast or contraindicated from receiving therapeutic ultrasound, were excluded. Therapeutic ultrasound was applied for 10 minutes to the right breast and samples of 5 ml expressed human milk were collected pre and post ultrasound application. Protein, lactose, and fat concentrations were measured by the Bradford method, enzymatic spectroscopy, and creamatocrit. Statistical analysis included general linear mixed modelling.

There was no significant difference in human milk protein composition between measures taken pre and post ultrasound (mean difference, -0.64g/L; 95% CI [-1.93, 0.64], p = 0.328). There was no significant difference in human milk lactose composition (mean difference, -4.77g/L; 95% CI [-11.57, 2.03], p = 0.169) between measures taken pre and post ultrasound. There was a significant increase in human milk fat composition between measures taken pre and post ultrasound (mean difference, 1.36%; 95% CI [0.97, 1.75], p <0.001).

Therapeutic ultrasound applied to the healthy lactating breast does not adversely affect the protein, lactose, or fat concentrations of human milk.