Guide Note: Momnesia is believed to occur in mothers shortly after childbirth and it causes mental fuzziness and memory loss. USA Today reported on the condition on March 4, 2008. Researchers are unable to explain the way that motherhood affects a woman's memory but they are in agreement that a pattern is evident. Research has also shown that although fathers don't undergo the same severe changes that women do however they do experience a slight change in hormone levels.