Complications
The forceful spray of milk can cause the baby to consume too much milk too quickly as well as to swallow air during the period of rapid swallowing following the let-down. The speed of the flow of milk into the mouth can cause the baby to react with reduced nursing times and aversion to nursing often described by mothers as "fussiness", "colicky", "dislikes nursing", or "is weaning". Some babies, especially those of approximately 2-4 months of age, become increasingly upset with the spray of milk which may increase their aversion to nursing to the point of refusing the breast (a nursing strike).
Overactive let-down can be a part of a constellation of symptoms that make up Oversupply Syndrome or Oversupply Colic. Babies coping with OSS, gain weight quickly in the early months, even while nursing for short period. Some OSS babies sleep for surprisingly long periods of time and depth, possibly due to an over-full feeling, while others have very disturbed sleep, possibly due to gastrointestinal pain.
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