Dr. Frances Oldham Kelsey, whose tireless efforts uncovered a link between the drug thalidomide and severe birth defects, has died at age 101.

In 1960, Kelsey was the new medical officer at the Food and Drug Administration when an application for FDA approval of the sedative Kevadon, the trade name of thalidomide, manufactured by drug company William S. Merrell Company of Cincinnati.

Thalidomide had already been sold to pregnant women in Europe and elsewhere as an anti-nausea drug to treat morning sickness, and Merrell wanted a license to do the same in the U.S.

As The New York Times reports, Kelsey asked for more information.

"Thus began a fateful test of wills. Merrell responded. Dr. Kelsey wanted more. Merrell complained to Dr. Kelsey's bosses, calling her a petty bureaucrat. She persisted. On it went. But by late 1961, the terrible evidence was pouring in." Thalidomide "was causing thousands of babies in Europe, Britain, Canada and the Middle East to be born with flipperlike arms and legs and other defects."

As The Washington Post adds, "[the] tragedy was largely averted in the United States, with much credit due to Kelsey. ... For a critical 19-month period, she fastidiously blocked its approval while drug company officials maligned her as a bureaucratic nitpicker."

The Post, in a front-page article published in 1962 described Kelsey as a "heroine" whose "skepticism and stubbornness ... prevented what could have been an appalling American tragedy."

Kelsey, a physician and pharmacologist, died on Aug. 7. Her daughter confirmed her death to The Washington Post, but did not cite a cause.

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