Zanin LL. Mother's daughter: transgenerationality of incest [Dissertation]. São Paulo: "Faculdade de Medicina, Universidade de São Paulo"; 2017.Sexual abuse in Brazil has become a public health problem not only because of the high incidence of this type of violence, but also because of its effects on the body and the psyche of those who suffer it. Incest is the most common form of sexual abuse and its consequences can reach future generations. There are few Brazilian studies that investigate sexually abusive experiences in parents of children and adolescents who have experienced sexual violence. This research carried out the survey of 346 medical records of families with a history of intrafamily sexual abuse supported at the Center for Studies and Attendance Related to Sexual Abuse (CEARAS), between 1993 and 2016, with the purpose of characterizing the population of the institution and verifying the repetition of the sexual abuse in the history of the family group, especially in the mother's life history. The quantitative methodology was used and psychoanalytic concepts of Freudian approach were presented to support the discussion. The survey revealed that the complaint of intrafamily sexual abuse occurred more frequently in girls (82%) when compared to boys (17%). The highest incidence of this form of violence occurred in childhood (0 to 12 years) for both girls (61.1%) and boys (80%). In most cases, during the childhood, the complainant, in both sexes, was the mother (44.2%). However, in the adolescence period of the girl, the mother (29.6%) and the adolescent herself (29.6%) reported in equal proportion. No male adolescent has made any reports. A great part of the sexual abuse occurred during a long period of time (42%). The most common type of sexual abuse was the libidinous act (73.3%), compared to the carnal conjunction (14%). The perpetrators of sexual violence were, in most cases, males (97.6%). In the girl's childhood, sexual abuse was perpetrated mostly by the father (51,5%), followed by relatives (17%) and stepfather (14%). In the boys' childhood, the father (56.3%), relatives (12.5%) and the mother (8.3%) were the people who most committed abuse. The results also revealed that in more than half the population of CEARAS (60%) other cases of sexual abuse occurred in previous generations and with other people of the same family. The occurrence of abusive sexual experiences not reported in the parents' life history was found in 87 (25%) cases. The history of abuse in parents of children or adolescents who have suffered sexual violence suggests the existence of the transgenerational phenomenon of incest. 71(20%) mothers, from our total sample, revealed to be victims of sexual abuse during their childhood or adolescence. Thus, the history of sexual abuse in the mother was considered a strong potential for the generational transmission of sexual abuse in the daughter. Incest is considered a cycle, which tends to repeat itself if it is not interdicted.