Prolonged separation from mother increases risk of breast cancer in young mice
 

Young mice that experienced the psychosocial stress of prolonged separation from their mothers had a higher incidence and faster onset of breast tumors compared with young mice who did not experience this stressful life event. Specifically, neonatal mice separated from their mothers for a prolonged period of time developed mammary tumors twice as fast as mice that experienced short or no maternal separation.

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