The IVF Museum · Pioneers · Gregory Pincus

Gregory Pincus

9 April 1903 to 22 August 1967 · Woodbine, New Jersey, to Boston

He grew rabbit eggs outside the body in the 1930s, and went on to give the world the contraceptive pill.

Gregory Pincus was born in 1903 in Woodbine, New Jersey, to Russian Jewish immigrant parents. He trained in genetics and physiology at Cornell and Harvard, and spent fellowship years in Berlin and at Cambridge, where he worked with F. H. A. Marshall and John Hammond. Back at Harvard in the early 1930s, he asked whether the earliest stages of mammalian life could be made to happen outside the body.

In 1934 he and E. V. Enzmann reported that rabbit eggs exposed to sperm in glassware, then transferred to foster mothers, had given live young. In 1935 they showed that rabbit eggs taken from their follicles would mature on their own in culture, an observation that underlies the maturing of eggs in the laboratory today. In 1939 he reported rabbits born from eggs activated without sperm. His book The Eggs of Mammals (1936) summarised the young field. One of his errors had long consequences: in 1939, with B. Saunders, he reported that human eggs mature in culture in about the same time as a rodent's, around twelve hours. The true figure is nearer thirty-six, and Robert Edwards spent years finding it.

Those claims were questioned, and others could not reproduce them on demand. His colleague M. C. Chang spent years putting rabbit IVF on firm ground, and succeeded beyond doubt in 1959. Press coverage of his work was sensational and damaging, and in 1938 he left Harvard amid the controversy.

In 1944, with Hudson Hoagland, he founded the Worcester Foundation for Experimental Biology. In the early 1950s Margaret Sanger and Katharine Dexter McCormick backed him to develop a contraceptive pill. With Chang he showed that progesterone and new synthetic hormones stopped ovulation in animals, and with John Rock and Celso-Ramón Garcia he moved into clinical studies in Boston and large trials in Puerto Rico. In 1960 the United States approved the first oral contraceptive. His friends remembered an honest scientist who did not knowingly go beyond his facts.

We believe, therefore, that this is the first certain demonstration that mammalian eggs can be fertilized in vitro.Gregory Pincus and E. V. Enzmann, PNAS 1934

Life and work

• Cornell University, BS 1924; Harvard University, MS and ScD 1927
• National Research Council Fellow, Kaiser Wilhelm Institute, Berlin, and Cambridge, 1927 to 1930
• Harvard University, 1930 to 1938
• Clark University, 1938 to 1945; Guggenheim Fellow 1939 to 1941
• Co-founder, Worcester Foundation for Experimental Biology, 1944
• Member of the National Academy of Sciences, 1965

Key papers

1. Pincus G, Enzmann EV. Can mammalian eggs undergo normal development in vitro? PNAS 1934;20:121 to 122. ReadHis first claim of rabbit IVF.
2. Pincus G, Enzmann EV. The comparative behavior of mammalian eggs in vivo and in vitro. I. The activation of ovarian eggs. Journal of Experimental Medicine 1935;62:665 to 675. ReadEggs maturing on their own in culture.
3. Pincus G. The Eggs of Mammals. New York: Macmillan, 1936. Read the book
4. Pincus G, Saunders B. The comparative behavior of mammalian eggs in vivo and in vitro. VI. The maturation of human ovarian ova. Anatomical Record 1939;75:537 to 545. Read
5. Pincus G, Rock J, Garcia CR, Rice-Wray E, Paniagua M, Rodriguez I. Fertility control with oral medication. American Journal of Obstetrics and Gynecology 1958;75:1333 to 1346. ReadThe trials of the pill.
6. Pincus G. The Control of Fertility. New York: Academic Press, 1965. Read the book

See also M. C. Chang, John Rock and the Pioneers wing.

The IVF Museum · Pioneers · Gregory Pincus
Compiled with AI-assisted research and checked against the original sources. Undergoing peer review. Corrections are warmly welcomed.