I will agree as far as both parents having a serious and evenly weighted discussion about the potential future of a life but Brian your emphasis on a feeling of posession and savage vindictiveness definitively disqualifies you from responsible fatherhood.
A baby is until the development of cognition an extension of the mother's body. This is true. But I don't think it is fair to completely exclude the opinion of the father. Make no mistake the mother's physical and mental wellbeing are chief among my concerns but to completely cut out the other half of the creation of a life, particularly if they are willing and capable of taking responsibility for bringing a life into the world, is utterly unfair in a partnership barring medical and psycholigical concerns even if such an event brings that partnership to an end.
Just... Talk it out. Give a chance to plan and if one side is truly willing to commit to raising a child in the face of a break up consider their ability to follow through as long as their reasons surpass their own petty pathetic vanity.
Ultimately as it is a woman's body in question it is her call but please... just grant your partner the consideration of a true partner.