Who suggested that men have womb envy because they cannot give birth?

The correct answer is Karen Horney.

The psychiatrist Karen Horney when refuting Freud's claim of penis envy claimed that, womb envy is something that men strongly experience. Womb envy means that men envy women's ability to bear and feed children, and the experience of motherhood. Horney claimed that men compensate for their womb envy by taking up powerful positions and oppressing women.