The World Health Organization and UNICEF define the protection and support of breastfeeding as one of the key determinants of maternal and newborn health. Nipple cracks are common in the postpartum period and cause breastfeeding problems. If not addressed early, they can lead to interrupted or complete cessation of breastfeeding. It is important to develop methods for effective, safe, and mother-friendly care of nipple cracks. Various care approaches, such as lanolin, natural products, and hydrogels, have been described in the literature. However, evidence for non-invasive agents that support wound healing at the cellular level is limited. Evidence for LED light application is limited, and there is no evidence regarding the effect of topical oxygen application on nipple cracks.

This project is designed as a randomized controlled trial to investigate the effect of topical oxygen and LED light therapy applied to nipple cracks on wound healing, pain, and breastfeeding success. The study will be conducted at the Lactation Unit of Istanbul Haseki Training and Research Hospital, Ministry of Health, between March and December 2026. The sample size was calculated using the G*Power program; with an effect size of 0.20, a significance level of 5%, and a power of 80%, a total of 51 mothers will be included in the study. Participants will be divided into three groups using the block randomization method: Topical Oxygen (n=17), LED Light Therapy (n=17), and Control (n=17). Standard breastfeeding counseling will be provided to all groups. In addition to the intervention groups, topical oxygen will be applied at a flow rate of 10 liters per minute for 20 minutes; LED light therapy will be applied at 630 nm red and 850 nm infrared wavelengths, at an energy dose of 15.3 J/cm², for 5 minutes. Interventions will be performed on days 0, 3, and 7. Data will be collected using a personal information form, wound size measurement, Nipple Trauma Score, Visual Analog Scale, and LATCH score. The validity and reliability of the Nipple Trauma Score in Turkish will be assessed within the scope of the project.

To reduce measurement and analysis bias, support will be obtained from an independent observer and a statistician.

Inclusion Criteria:

• Individuals aged 18-40,
• Those who gave birth at term (37-42 weeks),
• Those whose baby was 0-28 days old at the first visit,
• Those diagnosed with nipple fissures,
• Breastfeeding their baby,
• Those who have had a single birth,
• Those without a diagnosis of psychiatric illness and who are not taking related medication.

Exclusion Criteria:

• Those with infection, mastitis, abscess, etc. accompanying nipple injury,
• Those who have started medical treatment for nipple injury,
• Those who are unable to continue breastfeeding,
• Those who feed their baby by expressing breast milk,
• Those who show any adverse reaction to photosensitivity or exposure to sunlight.

Eligibility is limited based on biological sex, as the study includes postpartum individuals who have given birth and are breastfeeding.