This study aimed to investigate whether potentially infanticidal violence by men toward their pregnant partners’ is motivated by jealousy, and hence paternity uncertainty. It was predicted that men who used potentially infanticidal violence (directing their physical aggression towards their pregnant partners’ abdominal region) would have younger partners as this is associated with greater reproductive value; would be in relationships of shorter duration as this may indicate less stable relationships; and would be more jealous and restrictive of their partner’s movements and friendships than violent men who directed their aggression to other regions of their pregnant partners’ body. Relationship behaviors were provided from 43 women in domestic violence shelters (n = 43), using measures of the following: (1) partner physical aggression (2) victim fear and injury, (3) areas of bodily assault (when pregnant and when not pregnant), (4) controlling behaviors, and (5) topics of disagreement. Violence directed towards the fetus was associated with shorter relationships where both partners were younger. In such relationships, there was more physical aggression from the male partner, he used more controlling behaviors to isolate his partner, and the partners had more disagreements arising from his jealousy, compared with when physical aggression was not directed towards the fetus. These findings are consistent with an infanticidal motive for men’s aggression directed towards their pregnant partners. If paternity uncertainty is a primary cause of this dangerous form of domestic violence, it should form an important element in any screening instrument.