Yes, and this is the reason behind the development of the rape kit used in hospitals. From the almighty wikipedia:
Evidence collection in the United States
In the United States, a typical evidence collection process for sexual assault victims is:
- A nurse explains the hospital's HIV testing procedure and why HIV testing is beneficial. The victim then decides whether or not to permit HIV testing. In many states, there is no charge to the victim for these services.
- Routine blood collection is done (to check for pregnancy or sexually transmitted diseases).
- The nurse documents any evidence of torn clothing or external injuries and takes photographs.
- The victim's clothing is collected and new clothes are provided.
- Any physical evidence from the rape scene (such as grass or leaves) is also collected.
- Hairs are collected: the nurse collects any loose hairs or debris in the pelvic area (looking for pubic hairs of the assailant). In some cases, some of the victim's pubic hairs are needed and 15-20 of the victim's head hairs (to differentiate the victim's hairs from the assailant's).
- Fingernail scrapings are collected for detection of blood or tissue.
- The nurse then examines the victim's perineum, thighs, abdomen, buttocks and facial area for evidence of semen and, if detected, it is collected.
- Several slides are made and swabs taken from the vaginal, anal, and oral areas to check for semen, sexually transmitted diseases, and infections.
- The hospital provides the victim with any preventive medicine necessary (for tetanus, sexually transmitted diseases, pregnancy, etc.).
- Medical personnel perform the pelvic exam. The victim may request to have the examination done by a person of the same gender.
The sexual assault kit is then sealed in a box and secured at the hospital until given to the police for further laboratory analysis. For the box to be used in criminal proceedings, it is vital that the
chain of custody and the integrity of the kit is preserved.
In order for a good case to be presented in front of a jury, evidence must be present that a struggle occurred to show that the act was not consensual. Showing evidence of penetration, then presenting evidence that there was a struggle, and then finally showing evidence of the accused being the attacker, is what the courts insist on having in order to prosecute.
I disagree that rape is something easy that a woman can prove. I have not heard of cases where a woman simply shows up at a local precinct, points a finger at a man, says he raped her, and the officers cuff the guy. They need initial evidence in order to further investigate, so men are not arrested as a rule simply because "she said so."
The difficulty in proving a rape case is where many victims get stiffed. Many times, there simply isn't enough evidence to prove guilt. Too often, victims remove evidence out of shock or shame, take too long to report, or refuse to be examined in order to prepare a rape kit (it's incredibly invasive, and to a recent rape victim, it can be too much in such a shocked and vulnerable state).
I didn't report my ex after I was raped by him, but a very brave woman did after he raped her. She followed all the procedures that put him behind bars as well as getting a good attorney in order to seal the deal with a solid case. I can tell you from experience that it is NOT easy.