The concept of guilt seems to have appeared so often in contexts related to parenting that some English native speakers use the expressions 'parent guilt' or 'parental guilt' to indicate the situation. Instead of a direct translation for the expression, you could focus on a bigger block of text, such as a sentence. As far as I understand the contexts (which can be pretty much grasped via a web search: https://www.google.com.br/search?q=parental+guilt&oq=parental+guilt&aqs=chrome..69i57j0l5.3587j0j7&sourceid=chrome&ie=UTF-8#q=parent+guilt), a parent can feel guilty of caring less for his/her child and more either for his/her career or for his wife/her husband. You get clumsy in trying not to let your own emotional problems interfere in your children's life quality and then you feel frustrated as a parent. An expression that might work in Portuguese seems to be 'senso de culpa por parte dos pais', even though it is too long. A key to find a good expression is to have a clear context. In that case, even 'senso de culpa dos pais' or 'senso de culpa da mãe' might fit, but again the context, surrounding words included, could help. Maybe 'autocobrança' could substitute 'senso de culpa'.

It depends on what you mean exactly. Would you put it in a context, please?

That is a hell of a good question, Daniel answered it better down the answer section

But what "Parental Guilt" means ?