The ESV Bible Blog discusses the literal rendering of the term for knowledge in sexual contexts. Some contemporary translations treat this as a mere euphemism for the physical act of sex. Since we don't use the word 'know' in English in this way, he argument goes, we should use an expression that says what really took place, a physical act of sex. I think this loses not just a connotation of what the original expression says. I think it loses the very reason that word was used to begin with. I do note that the ESV doesn't always keep the original word, as the post admits. It just treats this argument as presumptive, as I think it should be treated. Other factors might turn out to be more important in any given passage. I don't know if I'd always agree in particular cases, but I think that's the right approach.
However, I think one argument the post discusses but does not endorse seems to me to be too far, and I think what it shows is a deeper problem in translation to begin with. The argument is that translating the Hebrew word for knowledge in these contexts as "have relations with" is banal and does not capture the element of knowing in the original. Is this true? Maybe so, but if so then I wish it were not true. Has the sense of relationship and relating to someone completely gone out of expression "to have sexual relations"? If so, this is a further slide down a path we've already seen in the past. Intercourse was once a close sharing, of human interaction on a deep level. Now it's sex, and it's used in he clinical, banal way that "have relations with" is claimed to be used. Consider also the word 'intimacy'. We can say that two people were intimate, and we might just mean that they did the nasty in exactly the sense of performing the physical act, with no sense that they were close in any other way.