Akuyaku Ikka no Okugata, Shi ni Modori shite Kokoro wo Irekaeru

The story begins when Elain, the duchess of a family so treacherous it has even plotted to claim the throne, dies at the hands of her own daughter. She finds herself regretting her own villainy only at death's door, and realizes far too late the ruin that she has brought to her family name. However, she is surprised to regain consciousness — right in the middle of childbirth. She realizes quickly that she has been brought back in time 30 years to when she had her first son. Carrying her regrets and resolving to not die an ignoble death from her daughter, she works to change her ways and improve her life with her knowledge of the future. (Source: ANN)