ABSTRACT That katuk leaf (Sauropus androgynus (L). Merr) has good nutrition and is able to increase breastmilk production. The study of the effect of katuk leaf ethanol extract administration on prolactin hormone level in the breastfeeding white rats. The purpose of this study was to analyze the effect of katuk leaf ethanol extract administration on prolactin hormone level and oxytocin hormone level in the breastfeeding white rats. The type of the research is experimental with Post-Test Only Control Group design. The sample size consisted of 24 breastfeeding white rats which are divided into 4 groups, i.e. one control group and three treated groups (P1, P2 and P3), each given 24 mg, 48 mg and 72 mg katuk leaf ethanol extract. The research w...