Effect of a ginger-spiced millet-soya drink and breastfeeding education on prolactin levels and breast milk volumes in postpartum mothers in northern Ghana: a randomized controlled trial.

Abstract

Background: Exclusive breastfeeding is essential for optimal infant nutrition and health, yet many mothers experience concerns about insufficient milk supply. This study investigated the effects of a ginger-spiced millet-soya drink (Zim-So drink), selected for its rich content of phytoestrogens and cultural use as a galactagogue and breastfeeding education on breast milk volumes and prolactin levels to enhance breastfeeding experiences among postpartum mothers in Tamale, Northern Ghana.

Method: A randomized-controlled intervention study was conducted, with 75 participants randomly assigned to three groups: Zim-So drink (n = 25), breastfeeding education (n = 25), or control (n = 25). The sample size was determined using G-Power to detect a moderate-to-large effect (Cohen's d = 0.8) with 80% power and α = 0.05. Blinding was not feasible due to the type of intervention, but standardized procedures minimized observer bias. Breast milk volume was measured using a manual breast pump and standardized logging; serum prolactin levels were assessed using ELISA at baseline, Day 7, and Day 14. Statistical analysis was conducted using Analysis of Variance (ANOVA) followed by Tukey's post hoc test to determine significant differences among samples.

Results: The study found no significant baseline differences among groups, confirming their comparability. By Day 7 and Day 14, both the Zim-So drink and breastfeeding education groups showed significant improvements in breast milk volume and prolactin levels compared to the control. The Zim-So drink group demonstrated the largest effect size, with mean breast milk volume increasing by 24.9 mL (95% CI, 22.1-27.7) and prolactin levels by 25.0 ng/mL (95% CI, 22.0-28.0) at Day 14 compared to the control (p < 0.001), indicating a stronger and sustained impact on lactation outcomes.

Conclusion: This study highlights the importance of dietary and educational interventions in enhancing lactation. The Zim-So drink, formulated with culturally familiar and bioactive-rich ingredients, emerges as an effective, acceptable, and affordable galactagogue for breastfeeding mothers. These findings indicate that integrating traditional dietary supplementation with structured breastfeeding education within maternal healthcare systems offers a practical and cost-effective approach to enhancing breastfeeding outcomes, particularly in resource-limited settings.