What causes a person to feel like vomiting after having sex?

Uncertain: Some of my response is speculation. There are probably a # of possible reasons for nausea associated w sexual intercourse. Some women report nausea w deeper penile penetration ;/or rough sex. In this situation there may be pain which could trigger nausea. Indigestion ; acid reflux might be causative. Prostaglandins could play a role. In some situations – nausea or vomiting could be psychological.