Can a man who has had a vasectomy, has since confessed it to a priest, and was absolved, receive communion?
Anyone who has sinned mortally cannot receive Communion (see Catechism no. 1857 for conditions for mortal sin) until he or she is restored to a state of grace through the sacrament of confession.
*Catechism of the Catholic Church *:
1415 Anyone who desires to receive Christ in Eucharistic communion must be in the state of grace. Anyone aware of having sinned mortally must not receive communion without having received absolution in the sacrament of penance.