Conservative estimates indicate that 18–25% of women in the United States will be exposed to some form of sexual assault in their lifetime. A great number of these women will develop post-traumatic stress disorder (PTSD). The current study explores the relationship between emergency contraception (EC) administration and subsequent post-traumatic stress symptoms in female sexual assault (SA) survivors. In a study population of 111 participants, post-traumatic stress symptoms were assessed approximately six months after the SA. Women who were already taking hormonal contraception (HC) at the time of the SA and those who declined EC were compared to women who took either Ogestrel or Plan B following the SA. While the administration of traditional HC and both types of EC were associated with fewer intrusive symptoms, women who took Ogestrel reported significantly lower post-traumatic stress total symptom levels than did those who took Plan B or those who declined EC. The results suggest that the manipulation of sex hormone levels with HC and EC in the immediate aftermath of trauma may influence subsequent post-traumatic stress symptoms. The current results may be useful in guiding the choice of EC.