In addition to his pastoral duties, McHugh did graduate work in sociology at Fordham University in New York City from 1963 to 1965. He served as moderator of the Bergen County Catholic Physicians' Guild (1964–65) and of the Bergen County Catholic Nurses' Council (1963–65). He continued his studies in sociology at the Catholic University of America in Washington, D.C. from 1965 to 1967. In 1965, he joined the staff of the National Conference of Catholic Bishops, where he served as director of the Family Life Bureau (1965–75), director of the National Right to Life Committee (1967), and of the Office of Pro-Life Activities (1972–78). While in that position he caused controversy when in response to President Nixon's July 1969 proposal of federal funding of artificial contraception as a means of population control McHugh said the President's message was "a positive and constructive approach to the problem." He was named a papal chamberlain in 1971, and raised to the rank of honorary prelate in 1986.