WASHINGTON (AFP) ― Virginia Johnson, who with her ex-husband and research partner William Masters blazed new trails in the study of human sexuality, has died at the age of 88, U.S. media reported.

Saint Louis Public Radio said Thursday her death was confirmed by her son Scott Johnson and by a retirement home in the Missouri city where she lived.

The cause of death was not disclosed.

Born in the Midwestern state into a family with Mormon roots, Johnson met Masters, an obstetrician-gynecologist 10 years her senior, in 1957 at Western University in Saint Louis, where he hired her as a research assistant.

With polygraph-like instruments and hundreds of volunteers, Masters and Johnson researched what they called a four-stage “sexual response cycle” that they documented in best-selling books in the 1960s.

In 1964 they set up a non-profit research center in Saint Louis that came to be known as the Masters and Johnson Institute.

It closed its doors after 30 years when Masters ― who died in 2001 at age 85 ― retired.

Masters and Johnson’s research helped stir the so-called “sexual revolution” in the United States, landed them on the cover of Time magazine in 1970 and brought Hollywood stars to their doorstep seeking help with their sex lives.

The duo married in 1971, but divorced in 1992.

Their life and work is the subject of a one-hour television drama, “Masters of Sex,” starring Michael Sheen and Lizzy Caplan, which is scheduled to premiere in September on the Showtime cable channel.