A lot of people also believe that men with bigger penises are better at making their partners feel good when they are having sex. For heterosexual men, this is because it is thought that when the penis can go further into the vagina, this helps the woman have a better orgasm. Scientists are not sure whether this is true or not. Some research shows that the most sensitive area of the female sex organs includes the vulva, clitoris and the part of the vagina nearest the outside of a woman's body. There are also parts of the clitoris inside the vulva and vagina. Therefore, most men's penises are long enough to make their partners feel good during sex. Also, some studies say it is not how long but how thick a penis is that decides how well it excites a woman sexually.