Clitoris- this is a very sensitive organ located in the opening of the vagina.  It is not directly connected to reproduction, but it is most definitely implicated in orgasms.  Many women need clitoral stimulation in order to achieve a single or multiple orgasms.

Perineum - this stretch of hairless skin runs from the bottom of the vagina, backwards to the anus.  It is also considered quite sensitive and responsive to sexual stimulation.

Clearly the internal organs lend themselves to dysfunction/abnormalities and possible disruption of normal fertility.  Ovarian cyats, blocked Fallopian tubes, fibroids in the uterus, endometriosis, and a cervix that has a different anatomical orientation or that remains open are just a few of the problems that can interfere with a healthy pregnancy.  Inadequate stimulation by your sexual partner, a small vaginal opening, lack of lubrication can interfere with sexual pleasure.