The IVF Museum · Pioneers · M. C. Chang

M. C. Chang

10 October 1908 to 5 June 1991 · Shanxi, China, to Worcester, Massachusetts

He proved, with black rabbits born to a white mother, that a mammal could begin life in a dish.

Min Chueh Chang grew up in Shanxi province and studied animal psychology at Tsinghua University, graduating in 1933. A national fellowship brought him to Britain in 1938, first to Edinburgh and then to Cambridge, where he worked with Arthur Walton on ram sperm and took his doctorate in 1941.

After the war he sought a one-year fellowship with Gregory Pincus to learn in vitro fertilisation, meaning to return to China. He arrived at the newly founded Worcester Foundation for Experimental Biology in 1945 and stayed for the rest of his life, serving for a time, by his own account, as its night watchman. Pincus had reported in 1934 that rabbit eggs fertilised in a dish gave live young, but Chang could not repeat the results, and set out to solve the problem properly.

His key insight concerned the sperm. In 1951 Chang, and independently Colin Austin in Australia, showed that sperm must spend time in the female reproductive tract before they can fertilise an egg. Austin named the process capacitation the following year.

In 1959 Chang published Fertilization of rabbit ova in vitro in Nature. He fertilised eggs from black rabbits with capacitated sperm from a black male, and transferred the embryos into a white doe. The young were black. Their coat colour ruled out any chance that fertilisation had happened inside the mother, and the experiment is widely regarded as the first unequivocal proof of IVF in a mammal with live births. It built on work in France by Moricard, and by Dauzier and Thibault. In 1963 he and Ryuzo Yanagimachi went on to fertilise hamster eggs in a dish.

From 1951 to 1956 Chang also tested steroids in laboratory animals as oral contraceptives, work that underpinned Pincus's development of the pill. He worked with his own hands at the bench throughout his career.

We have achieved a good deal towards the understanding of mammalian fertilization by simple biological experimentation.M. C. Chang, in a late review, as quoted by Roy Greep in his National Academy of Sciences memoir

Life and work

• Tsinghua University, BSc 1933
• University of Edinburgh, 1938; University of Cambridge, PhD 1941
• Worcester Foundation for Experimental Biology, Shrewsbury, Massachusetts, from 1945
• Lasker Award 1954; Marshall Medal 1971; member of the National Academy of Sciences 1990

Key papers

1. Chang MC. Fertilizing capacity of spermatozoa deposited into the Fallopian tubes. Nature 1951;168:697 to 698. ReadThe co-discovery of capacitation.
2. Pincus G, Chang MC, Zarrow MX, Hafez ESE, Merrill A. Studies of the biological activity of certain 19-nor steroids in female animals. Endocrinology 1956;59:695 to 707. ReadPart of the animal work behind the contraceptive pill.
3. Chang MC. Capacitation of rabbit spermatozoa in the uterus with special reference to the reproductive phases of the female. Endocrinology 1958;63:619 to 628. Read
4. Chang MC. Fertilization of rabbit ova in vitro. Nature 1959;184:466 to 467. ReadThe black rabbits: the first unequivocal mammalian IVF with live births.
5. Yanagimachi R, Chang MC. Fertilization of hamster eggs in vitro. Nature 1963;200:281 to 282. Read
6. Chang MC. The meaning of sperm capacitation: a historical perspective. Journal of Andrology 1984;5:45 to 50. ReadHis own account of the discovery.

See also The Animal Work and the Pioneers wing.

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