1. Introduction
n the recent COVID-19 pandemic, there have been many concerns about mother-to-child transmission of the virus during pregnancy and after delivery [19]. This issue is most important because of the simultaneous management of mother and baby after delivery and the importance of breastfeeding. Given that breastfeeding is the golden key to maternal and infant health, considering the recommendations of the World Health Organization (WHO) on exclusive breastfeeding in the first 6 months of life [11, 12], and due to the weakness and lack of development of the immune system in infants, especially premature infants, the importance of breastfeeding during the COVID-19 pandemic is doubled. COVID-19 is still unknown, and studies showing that the virus is not present in breast milk are very limited. This study aims to review the latest studies on breastfeeding during the COVID-19 pandemic.
2. Materials and Methods
This is a review study conducted on studies conducted on breastfeeding during the COVID-19 pandemic from December 2019 to May 2020. The search was conducted in SID, PubMed, Scopus, Science Direct, Google Scholar, Ovid, MagIran databases using following keywords in Persian and English:New coronavirus, COVID-19, Breast milk, and Breastfeeding. The collected articles entered EndNote and duplicate articles were removed. Then, the titles and abstracts of the articles read and the articles whose full texts were available were selected. Important points and materials were extracted from them and after collecting the desired materials, duplicate contents were removed and the remaining materials were reported. This article presents the latest guidelines of WHO and the Centers for Disease Control (CDC) on breastfeeding during the COVID-19 pandemic.
3. Results
Studies showed that there is no evidence of the presence of COVID-19 in breast milk or its transmission through breastfeeding from the mothers with or suspected of COVID-19 [14, 15, 16, 17, 18, 19, 20, 21, 22]. If the mother does not have severe symptoms of COVID-19 with a definitive diagnosis, breastfeeding should be performed with following health tips, precautionary measures to prevent and control the infection, breathing precautions, and hand washing. If the mother is suspected of having COVID-19 and is able to care for her baby, the mother and baby can be in the same room, but it is recommended that the baby be two meters away from the mother, and all breast care and breastfeeding should be done with maintaining hygiene tips (washing hands and wearing a three-layer surgical mask). If it is not possible to separate and place the baby in another room, the baby should be at least two meters away from the mother and a curtain should be hung from the ceiling between the mother and the baby. If the mother has a severe COVID-19 infection, the baby should be temporarily separated and kept in another room by a healthy trained person, and the mother should express her breast milk for the baby by implementing all precautionary infection prevention measures. If breast milk is not available, the milk donated by other mothers (prepared from the human milk bank) should be used to feed the baby [14, 20, 21].
4. Discussion and Conclusion
Due to the positive effects of breast milk on maternal and infant health, the (WHO) recommends it as a high quality biological fluid and recommends that infants be exclusively breastfed until six months of age [11]. Breast milk contains a variety of biological agents that boost the function of the baby’s immune system [12, 13]. In all cases of COVID-19 (confirmed or suspected), breast-feeding should be continued in accordance with hygiene and respiratory precautions. Before and after contact with the baby, hands should be thoroughly washed with soap or disinfectant liquid, and a surgery mask should be used when feeding the baby and does not necessarily require the use of the N95 masks. Touched surfaces should also be cleaned and disinfected routinely. A mother with severe symptoms of COVID-19 (respiratory distress, high fever, and cough) who is unable to care for her baby, should be temporarily separated from her baby and cared for by a healthy caregiver. During this time, the baby should be fed by the mother’s fresh breast milk. The mother should be told to express and store her milk at intervals of 2-3 hours in accordance with hygiene tips so that the flow of milk is not interrupted. If the mother does not want to breastfeed, donated milk prepared from the human milk bank should be used to feed the baby.
Given that studies showing the absence of COVID-19 virus in breast milk are very limited, this study provides the breastfeeding tips during the current COVID-19 pandemic. While many unknowns of this emerging disease are still present, further studies are needed on managing breastfeeding in this pandemic.

Ethical Considerations
Compliance with ethical guidelines
Ethical principles have been observed according to the instructions of the National Ethics Committee and the COPE regulations.

Funding
This research did not receive any grant from funding agencies in the public, commercial, or non-profit sectors. 

Authors' contributions
The authors observed the criteria of the International Committee of Medical Journal Editors (ICMJE).

Conflicts of interest
The authors declare no conflict of interest.

Acknowledgements
The authors would like to thank Dr. Vahid Zamanzadeh, dean of School of Nursing and Midwifery, University of Tabriz, and Dr. Saadaleh Yeganeh Doost for their cooperation.


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