Q: Are risks different for men vs women?

A: In heterosexual vaginal or anal sex, if other factors are equal, a woman has a biologically higher risk of infection compared to a man.

  • The surface area of the vagina or anus is far greater than the surface area of the penis.
  • The risks of tears to the vagina or anus during sex is greater as the these inner linings are more delicate than the skin on the penis.
  • The length of time of exposure of the vagina or anus to semen is greater than the time the penis is exposed to the vaginal fluid or rectal mucosa.

Q: Are risks similar for insertive vs receptive anal sex?

A: The risk for anal sex, if other factors are equal, is greater for a receptive partner compared to an insertive partner.

  • The surface area inside of the anus, is larger than the surface area of the penis
  • The risks of tears to the anus during sex is greater as the membrane on the inside of the anus is more delicate than the skin on the penis
  • Pre-cum and cum will stay in the receptive partner for longer than the insertive partner is in contact with rectal tissue and mucosa.

1 June 2016