Dr. Gladys Neidig Conly, 61, a United Nations economist who had worked here with the Pan American Health Organization from 1963 to 1976, died of cancer Sept. 29 in a hospital in New York City. She lived in New York City.

During her years in Washington, she had directed an economic study on the long-term impact of malaria in various parts of the world, studying the relationship between the disease and economic productivity.

In 1976, she went to New York City to join the United Nations' economic and social affairs department. She retired from the UN in November 1980 as chief of its International Civil Service Commission's cost of living section.

Dr. Conly was a native of Pennsylvania and 1942 honors graduate of the University of Rochester. She earned a master's degree in economics at Columbia University and a doctoral degree in economics at the University of Wisconsin.

She began her career with the UN as a statistician with the International Labor Organization in Geneva, Switzerland, in 1950, and then worked at United Nations headquarters in New York before coming to Washington.

Survivors include her husband, Michael O'Connell of New York and Japan; a daughter, Kathleen O'Connell of New York City, and a sister, Phyllis Helfand of Tiburon, Calif.