The idea of grandma and grandpa having sex in nursing homes gets a reaction of ugh! from many people, yet it is precisely this vision of sex in old age that the above myth seeks to control. I have found that among the sex for procreation only crowd that some believe that sex should stop once a woman is beyond childbearing years. Others believe that sex in the post menopausal years is good, only if the couple is open to the idea that God might work a miracle to cause pregnancy. We can see from this myth how people have taken what God has not forbidden and made a prohibition out of it. Then, in order to wiggle themselves out of the trap and snare they have created for themselves, they come up with this "open to life" option which in their minds make sex in the postmenopausal years licit. When I read and hear these wranglings, I just quietly laugh within myself, because nothing in scripture stops post menopausal women from engaging in sex - nothing!
Elizabeth and Zacharias, the parents of John the Baptist, were having sex in their old age, well past menopause, without giving any thought to the possibility that Elizabeth could get pregnant. I know this is so because the Bible says that Elizabeth was barren, and they were both very old.
"And they were both righteous before God, walking in all the commandments and ordinances of the Lord blameless. And they had no child, because that Elisabeth was barren, and they both were now well stricken in years (Luke 1:6-7)."
God wanted to bless their sexual union with a son, and so God sent the angel Gabriel with the message that Elizabeth would become pregnant. Zecharias totally disbelieved Gabriel because both he and his wife were well past childbearing age. We read, "And Zacharias said unto the angel, Whereby shall I know this? for I am an old man, and my wife well stricken in years (Luke 1:18). Because of his disbelief, Zecharias was struck dumb by God. It says here:
"And the angel answering said unto him, I am Gabriel, that stand in the presence of God; and am sent to speak unto thee, and to shew thee these glad tidings. And, behold, thou shalt be dumb, and not able to speak, until the day that these things shall be performed, because thou believest not my words, which shall be fulfilled in their season" (Luke 1:19-20).
Was Zecharias commiting a sin when he had sex with his wife even though he did not believe she could get pregnant? Absolutely not! God blessed their union, even though Zecharias was not "open to life" during sex.
Look, unless God personally tells you Himself that you will get pregnant in your post-menopausal years, don't even try to waste time worrying whether or not you have committed a sin by engaging in sex with your spouse without being "open to life." People who preach this "open to life' doctrine are only fooling themselves, because according to the laws of nature, it is impossible for a post menopausal woman to get pregnant without miraculous, divine intervention. To which of us millions/billions of women did God promise children in old age? Was He not the one who created the laws of nature to stop childbearing in the post menopausal years? From what I understand in the Bible, God does not just perform a miracle for the sake of performing miracles, in order to please our whims and fancies. He always perform a miracle for a divine purpose, and in the case of Elizabeth and Zecharias, it was to make them the parents of the forerunner of the Messiah, Jesus Christ.
Let me conclude by saying that we do not have to worry at all if grandma and grandpa are still enjoying sex. As long as they are physically able, and are healthy enough to enjoy it, then they should go right ahead! God's word gives them permission.