Linda M. Williams said this quote

One hundred twenty-nine women with previously documented histories of sexual victimization in childhood were interviewed and asked detailed questions about their abuse histories to answer the question Do people actually forget traumatic events such as child sexual abuse, and if so, how common is such forgetting? A large proportion of the women (38%) did not recall the abuse that had been reported 17 years earlier. Women who were younger at the time of the abuse and those who were molested by someone they knew were more likely to have no recall of the abuse. The implications for research and practice are discussed. Long periods with no memory of abuse should not be regarded as evidence that the abuse did not occur. Journal of Consulting and Clinical Psychology, Vol 62(6), Dec 1994, 1167-1176