RESUMEN
Objective: To understand the risks of posttraumatic stress disorder (PTSD) development in the next generation of PTSD patients, we conducted a review on the biological, but not genetic, evidence of transgenerational transmission of PTSD vulnerability. Methods: Pertinent articles published from 1985 to September 2011 were searched using online academic search engines, including MEDLINE, EMBASE, ScienceDirect, OVID, PsycLIT, and SCOPUS, and a non-systematic review was conducted. Results: There is paradoxical evidence that hypothalamic-pituitary-adrenal axis changes in PTSD patients may also be evident in their offspring. This effect and biological vulnerability to PTSD may be transmitted across generations through maternal epigenetic programming during pregnancy. The samples of most studies, which were not large enough and represented the outcome of few research groups, consisted of a specific type of patients with a particular trauma. Conclusions: There is still a need to conduct studies in other geographical areas with different genetic background and larger samples considering different types of trauma other than those specified in the current literature, so as to strengthen the evidence of transgenerational transmission of PTSD vulnerability. .