This question is about the following explanation from this page at lds.org:
“If Adam had not transgressed he would not have fallen, but he would have remained in the garden of Eden. And all things which were created must have remained in the same state in which they were after they were created; and they must have remained forever, and had no end.
“And [Adam and Eve] would have had no children; wherefore they would have remained in a state of innocence, having no joy, for they knew no misery; doing no good, for they knew no sin.
And the passage in Genesis 3:16 (NIV) records the following statement from God to Eve after the "fall":
To the woman he said, “I will make your pains in childbearing very severe;with painful labor you will give birth to children. Your desire will be for your husband, and he will rule over you.”
The question is: why would God make Eve's childbearing severe and painful after the fall, if the fall was needed for them to accomplish God's plan?
(I would have thought the verbal expression from God in this case should then have been something along the lines of "Yesss! Congrats! You chose well, both of you. Now go forth and multiply.")