1843

Scientists discover that conception takes place when a sperm from the male reproductive system enters an ovum.

1873

The book Sex in Education, written by Harvard doctor Edward Clarke, argues that having a college education contributes to sterility among young women.

1884

In the first recorded case of artificial insemination by donor, Philadelphia physician William Pancoast treats a couple's infertility by injecting sperm from a medical student into the woman while she is under anesthesia; she gives birth to a boy nine months later. Pancoast never tells the woman what he has done, and only shares the information with her husband several years later.

1906

Surgeon Robert Tuttle Morris, who has been conducting partial "ovarian transplantations" from healthy women to those unable to have children, witnesses the first (and only) successful pregnancy in a recipient.

1910

Howard Jones, whose work with wife Georgeanna in the field of IVF will lead to America's first "test tube baby," is born in Baltimore. Coincidentally, Georgeanna's father is the obstetrician who delivers Howard.

Former president Theodore Roosevelt declares, "The greatest of all curses is the curse of sterility; and the severest of all condemnations should be ... visited upon willful sterility."

1917

September 10: John Del-Zio, who with his wife will become the first American couple to seek IVF treatment, is born.

1926

Rock, who has graduated from Harvard Medical School, opens an infertility clinic at the Free Hospital for Women in Brookline, Massachusetts.

1932

Aldous Huxley's futurist novel Brave New World is published; it depicts a bleak society populated by test tube babies and shapes public perceptions of the subject.

1937

An unsigned editorial in the New England Journal of Medicine, written by John Rock, praises the possibilities of IVF: "What a boon for the barren woman with closed tubes!" A year later Rock decides to attempt such fertilization in humans, hiring Pincus' former technician Miriam Menkin as a research assistant.

1944

In the six years since beginning their experiments, Rock and Menkin have collected some 800 ova and tried unsuccessfully to fertilize 138 of them. Between February and April, however, Menkin allows the egg and sperm to remain in contact for a longer period and succeeds in fertilizing four ova. This marks the first successful IVF of human eggs. Rock and Menkin do not attempt to implant the fertilized eggs in a woman. The published account of the research generates great interest.

1951

Physician Landrum Shettles duplicates the Rock-Menkin experiments at Columbia-Presbyterian Hospital in New York City.

1960

Shettles publishes Ovum Humanum, a book containing some of the more than 1,000 photographs he has taken of human eggs as they develop.

1962

Shettles will later claim that in this year he transplanted a fertilized egg into a woman's uterus, resulting in a pregnancy. If true, this would be a landmark event, but Shettles' claim is never substantiated.