Blocked ducts can cause a decrease in milk flow and milk supply. Blocked ducts if uncleared will cause mastitis.
To encourage milk supply is to encourage latching or pump at constant timing and intervals ie every feeding time and in the wee hours as well.
Massage your breasts before you latch or pump to facilitate letdowns and smooth milk flow.
Do watch your diet as some foods will cause your milk flow to decrease and subsequently stop.
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