ObjectiveTo investigate the effect of lanolin on nipple pain and trauma in breastfeeding after application of a health education. MethodRandomized controlled clinical trial, with two arms, open, with 66 participants during prenatal care in the primary health care network in Goiania – Goias, Brazil. Participants were randomized (1:1) using computer generated numbers in both experimental group (EG) and control group (CG). The EG received lanolin and health education on breastfeeding at two different times with clinical demonstration using cloth didactic breast and illustrative album as the intervention, while the CG received standard health education. Health education was carried out by the same researchers in both groups. Measurement of pain, nipple trauma, and breastfeeding technique occurred on postpartum day eight. The analysis included descriptive statistics and inferential analysis by means chi-square or Fisher test, and Student's t-test, significance level set at 0.05. ResultsA majority of the participants experienced no nipple trauma (59.1%) in both groups, and 60.6% of women experienced pain. In both groups, women showed favorable breastfeeding behaviors, except in the condition of the breasts. There were no significant differences between groups in pain prevention (p=0.61), nipple lesions (p=0.21), and breastfeeding technique (p>0.05). ConclusionIt is not clear whether the intervention, lanolin combined with health education, has a positive effect on the prevention of nipple pain and trauma. Further research is needed to elucidate this question.Registration number: RBR-7tvhq8.Registry website: http://www.ensaiosclinicos.gov.br/