Immortal Infertility

So you're given the ability to live forever and now you want to become a parent...and then you find out that you can't sire or even have children. Well, that totally sucks! However, for those who become immortal and either want to live hedonistically or just see the possibility that whatever children they may have may not inherit immortality, this may come as a blessing.

The reason for this is that a race that reproduces but doesn't die will eventually overcrowd the world. Also, immortal characters aren't as unique if there are too many of them.

Comic Books

 * Marvel Comics' The Eternals are not only immortal but nearly indestructible as well; however they can only have Eternal children with other Eternals, and even then, only once every millennium or so.

Film

 * The Immortals of the Highlander series of films face this trope as the downside of their having immortality.

Religion

 * Implied through Jesus' teachings in the Gospels that those who are worthy of the resurrection will "neither marry nor be given in marriage, but will be like the angels in heaven", indicating that there won't even be the desire for sexual intercourse among believers in their resurrected forms.
 * Sometimes used by Bible students to argue the case that the "sons of God" in Genesis chapter 6 could not be angels, but rather be the children of Seth's lineage marrying those of Cain's lineage (the "daughters of men").
 * This doesn't stop an Other Light member in the Left Behind book Kingdom Come from trying to impregnate a female "glorified" through an Attempted Rape that God foils by causing him to die in her arms before being incinerated.