Table 4.

List of factors and reported impacts on donation sustainability at the micro, meso, and macro levels.

30 Factors (at the Micro, Meso, and Macro Levels)	Reported Impact on Donation Sustainability *	Study Design and Reference (Cross Sectional Design Unless Otherwise Noted)
Micro Level (Donors, Their Infants and Families)
□Duration of donation	+	[27,34]
□Start of donation	+	[35]
□Preterm infant (gestational age)	+	Cross sectional & cohort study [27,28,35]
□Birth weight	−	[34]
□Admission to NICU	+	[31]
□Thrush in the infant	+	[26]
□Baby feeding frequency	+/−	[26]
□Growth of the baby	−	[32]
□Maternal age	+/−	[32,34]
□Number of pregnancies	+	[33]
□Education level	+	[33]
□Profession	+/−	[34]
□Self-hydration	+/−	[26]
□Diet	+/−	[26]
□Physical fatigue	−	[26]
□Presence of negative emotions	−	[26]
□Motivated to donate by having an excess of milk	+	[32]
□Motivated to donate by having to pump to stimulate lactation	+	[32]
□Donor’s availability of time	+/−	[26]
□Experience of breastfeeding simultaneously	−	Qualitative [29]
□Frequency of milk expression	+	[26]
□Nothing interferes with milk production	+	[26]
□Time of day for expressing milk	+	[26]
□Family support for donation	+	Qualitative [29]
□Mother’ routines (going out, contraceptive use, return to work)	−	[26]
□Previous milk donation history	+	[35]
Meso level (milk bank level)
□Milk bank support to donation	+	Qualitative [29]
□Work impact and support	−	Qualitative [29]
□Distance to milk bank	−	Qualitative [29]
□Human resources of HMB	−	Qualitative [30]
Macro level (system)
None reported

* (+) increases; (−) decreases.