It is narrated from Mujahid, may Allah have mercy on him: The meaning of «﴿فَأْتُوهُنَّمِنْحَيْثُأَمَرَكُمُاللَّهُ﴾»[بقره: 222/2] is that they have been commanded that after purification, fulfill your need at the same place from which you were prevented. (That is, intercourse is permitted and avoid the anus.)
Hadith Referenceسنن دارمي / من كتاب الطهارة / 1157