Objectives: This study aimed to compare the effects of green cumin (Cuminum cyminum) and nettle (Urtica dioica L.) oral drops on the indicators of breast milk adequacy in lactating mothers. Due to the presence of phytoestrogens in the combinations of cumin and nettle, it is stipulated that they may have milk-increasing properties.

Methods: A triple-blind, randomised, controlled clinical trial was conducted on 117 lactating mothers who had given birth to healthy infants aged 10-15 days and who received cumin oral drops (n = 39), nettle oral drops (n = 39) or placebo (n = 39) from August 2020 to March 2021. The participants were recruited from a regional public health care centre affiliated with Iran University of Medical Sciences of Tehran, Tehran, Iran. The 3 study groups received 15 drops thrice a day for 4 weeks. Infant weight, breastfeeding frequency, number of wet diapers, diaper weight and frequency of infant defecation were evaluated before and after the intervention.

Results: At the beginning of the trial, no statistically significant differences were observed between the 3 groups for infant weight (P = 0.891), breastfeeding frequency (P = 0.921), number of wet diapers (P = 0.783), diaper weight (P = 0.841) and frequency of infant defecation (P = 0.898). However, following the intervention, the mean scores of all indicators were significantly higher in the experimental groups than in the placebo group (P <0.001). In addition, all the indicators in the cumin group increased significantly compared to those in the nettle group (P <0.001).

Conclusion: Considering the effectiveness of cumin and nettle drops in increasing milk and the availability of these native plants in Iran, it is suggested that they, especially cumin, be used postpartum to increase breast milk production.