The Cubs placed Thompson on the paternity list prior to Wednesday's game against the Giants, Mike McGraw of the Chicago Daily Herald reports.
After striking out the side in Tuesday's 5-2 win to net his first save of the season, Thompson will be away from the team for at least the next 1-to-3 games following the birth of his son earlier Wednesday. The Cubs called up right-hander Porter Hodge from Triple-A Iowa to take Thompson's spot in the bullpen.