Psychological harm
Child sexual abuse can result in both short-term and long-term harm, including psychopathology in later life. Psychological, emotional, physical, and social effects include depression, post-traumatic stress disorder, anxiety, eating disorders, poor self-esteem, dissociative and anxiety disorders; general psychological distress and disorders such as somatization, neurosis, chronic pain, sexualized behavior, school/learning problems; and behavior problems including substance abuse, self-destructive behaviour, animal cruelty, crime in adulthood and suicide. A specific characteristic pattern of symptoms has not been identified and there are several hypotheses about the causality of these associations.
Long term negative effects on development leading to repeated or additional victimization in adulthood are also associated with child sexual abuse. Studies have established a causal relationship between childhood sexual abuse and certain specific areas of adult psychopathology, including suicidality, antisocial behavior, PTSD, anxiety and alcoholism. Adults with a history of abuse as a child, especially sexual abuse, are more likely than people with no history of abuse to become frequent users of emergency and medical care services. A study comparing middle-aged women who were abused as children with non-abused counterparts found significantly higher health care costs for the former.
Sexually abused children suffer from more psychological symptoms than children who have not been abused; studies have found symptoms in 51% to 79% of sexually abused children. The risk of harm is greater if the abuser is a relative, if the abuse involves intercourse or attempted intercourse, or if threats or force are used. The level of harm may also be affected by various factors such as penetration, duration and frequency of abuse, and use of force. The social stigma of child sexual abuse may compound the psychological harm to children, and adverse outcomes are less likely for abused children who have supportive family environments.
Dissociation and posttraumatic stress disorder (PTSD)
Child abuse, including sexual abuse, especially chronic abuse starting at early ages, has been found to be related to the development of high levels of dissociative symptoms, which includes amnesia for abuse memories. The level of dissociation has been found to be related to reported overwhelming sexual and physical abuse. When severe sexual abuse (penetration, several perpetrators, lasting more than one year) had occurred, dissociative symptoms were even more prominent.
Child sexual abuse independently predicts the number of symptoms for PTSD a person displays, after controlling for possible confounding variables, according to Widom (1999), who wrote "sexual abuse, perhaps more than other forms of childhood trauma, leads to dissociative problems ... these PTSD findings represent only part of the picture of the long-term psychiatric sequelae associated with early childhood victimization ... antisocial personality disorder, alcohol abuse, and other forms of psychopathology." Children may develop symptoms of post traumatic stress disorder resulting from child sexual abuse, even without actual or threatened injury or violence.
Research factors
Because child sexual abuse often occurs alongside other possibly confounding variables, such as poor family environment and physical abuse, some scholars argue it is important to control for those variables in studies which measure the effects of sexual abuse. In a 1998 review of related literature, Martin and Fleming state "The hypothesis advanced in this paper is that, in most cases, the fundamental damage inflicted by child sexual abuse is due to the child's developing capacities for trust, intimacy, agency and sexuality, and that many of the mental health problems of adult life associated with histories of child sexual abuse are second-order effects." Other studies have found an independent association of child sexual abuse with adverse psychological outcomes.
Kendler et al. (2000) found that most of the relationship between severe forms of child sexual abuse and adult psychopathology in their sample could not be explained by family discord, because the effect size of this association decreased only slightly after they controlled for possible confounding variables. Their examination of a small sample of CSA-discordant twins also supported a causal link between child sexual abuse and adult psychopathology; the CSA-exposed subjects had a consistently higher risk for psychopathologic disorders than their CSA non-exposed twins.
A 1998 meta-analysis by Rind et al. generated controversy by suggesting that child sexual abuse does not always cause pervasive harm, that some college students reported such encounters as positive experiences and that the extent of psychological damage depends on whether or not the child described the encounter as "consensual." The study was criticized for flawed methodology and conclusions. The US Congress condemned the study for its conclusions and for providing material used by pedophile organizations to justify their activities.
Physical harm
Injury
Depending on the age and size of the child, and the degree of force used, child sexual abuse may cause internal lacerations and bleeding. In severe cases, damage to internal organs may occur, which, in some cases, may cause death. Herman-Giddens et al. found six certain and six probable cases of death due to child sexual abuse in North Carolina between 1985 and 1994. The victims ranged in age from 2 months to 10 years. Causes of death included trauma to the genitalia or rectum and sexual mutilation.
Infections
Child sexual abuse may cause infections and sexually transmitted diseases. Depending on the age of the child, due to a lack of sufficient vaginal fluid, chances of infections are higher. Vaginitis has also been reported.
Neurological damage
Research has shown that traumatic stress, including stress caused by sexual abuse, causes notable changes in brain functioning and development. Various studies have suggested that severe child sexual abuse may have a deleterious effect on brain development. Ito et al. (1998) found "reversed hemispheric asymmetry and greater left hemisphere coherence in abused subjects;" Teicher et al. (1993) found that an increased likelihood of "ictal temporal lobe epilepsy-like symptoms" in abused subjects; Anderson et al. (2002) recorded abnormal transverse relaxation time in the cerebellar vermis of adults sexually abused in childhood; Teicher et al. (1993) found that child sexual abuse was associated with a reduced corpus callosum area; various studies have found an association of reduced volume of the left hippocampus with child sexual abuse; and Ito et al. (1993) found increased electrophysiological abnormalities in sexually abused children.
Some studies indicate that sexual or physical abuse in children can lead to the overexcitation of an undeveloped limbic system. Teicher et al. (1993) used the "Limbic System Checklist-33" to measure ictal temporal lobe epilepsy-like symptoms in 253 adults. Reports of child sexual abuse were associated with a 49% increase to LSCL-33 scores, 11% higher than the associated increase of self-reported physical abuse. Reports of both physical and sexual abuse were associated with a 113% increase. Male and female victims were similarly affected.
Navalta et al. (2006) found that the self-reported math Scholastic Aptitude Test scores of their sample of women with a history of repeated child sexual abuse were significantly lower than the self-reported math SAT scores of their non-abused sample. Because the abused subjects verbal SAT scores were high, they hypothesized that the low math SAT scores could "stem from a defect in hemispheric integration." They also found a strong association between short term memory impairments for all categories tested (verbal, visual, and global) and the duration of the abuse.