Background The most common type of feeding for infants is breastfeeding. Since breastfeeding mothers have low levels of breastfeeding knowledge, proper Health workers' support can play an effective role in raising mother's awareness and enhancing exclusive nutrition. This study aimed to evaluate the effect of telephone counseling during the postpartum period on exclusive breastfeeding. Materials and Methods: This quasi-experimental study was conducted on ۱۷۰ breastfed women referred to the ۲ selected health centers of Mazandaran University of Medical Sciences in ۲۰۱۸. The participants were randomly allocated into two equal groups (۷۵ individuals each). The participants in the intervention group received telephone counseling by one midwifery expert. The control group received routine care. Data were collected using a questionnaire including demographic characteristics and a breastfeeding check-list. Exclusive breastfeeding
rates were recorded two and six months after childbirth in both groups. Data were analyzed using SPSS software version ۲۴.۰. Results: A total of ۱۶۵ mothers participants in this study. Based on the results, exclusive breastfeeding rate was ۶۱% in treatment group and ۳۹.۸% in control group which was statistically significant (p=۰.۰۰۶). In addition, ۲۴ neonates (۲۸.۹%) of the newborns in the control group and ۱۹ (۲۳.۲%) in the intervention group were fed to the breastfeeding. This difference was statistically significant and indicates that the intervention Telephone counseling
in postpartum period has a positive effect on exclusive breastfeeding (p = ۰.۰۲۷). Conclusion Based on the results, using a counseling program in this study led to an increase in exclusive breastfeeding in newborns. Pre and postpartum and lactation care for both mother and infant can increase health and exclusive breastfeeding.