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COLLECTION Identifier: H MS c161

John C. Rock personal and professional papers


The John Rock papers, 1921-1985, are the product of Rock's activities as a fertility specialist and endocrine researcher at the Free Hospital for Women in Brookline, Mass. The collection includes correspondence, research studies, raw data, statistics, writings, lecture notes and outlines, lantern slides and photographs chronicling his research in oral contraceptives, in vitro fertilization, human embryo development, corpus luteum, artificial insemination, and the effect of temperature on the fecundity of human sperm.


  • 1921-1985 (inclusive)


Conditions Governing Access

Collection is open for research. Access requires advance notice. Access to personal and patient information is restricted to 80 years from the date of creation. These restrictions appear in Series I, II, III, VII. Folders containing patient information in their titles have been redacted in this finding aid to protect patient confidentiality. These folders are marked with [name redacted]. The end of the restriction period is noted with each restricted folder. Researchers may apply for access to restricted records. Consult Public Services for further information.

Boxes 1-25, 27-28, and 32-35 of the John Rock Papers are stored offsite. Boxes 26, 29-31, 36, and 11 oversized folders are stored in the Center for the History of Medicine's stacks. Researchers are advised to consult Public Services for further information concerning retrieval of material.

Conditions Governing Use

The Harvard Medical Library does not hold copyright on all materials in the collection. Researchers are responsible for identifying and contacting any third-party copyright holders for permission to reproduce or publish. For more information on the Center's use, publication, and reproduction policies, view our Reproductions and Use Policy.


43.2 cubic feet (40 record cartons, 2 document boxes, 2 legal document boxes, 3 flat oversized boxes, 1 slide box, and 11 oversized folders)

The John C. Rock Papers, 1921-1985, are the product of Rock’s clinical and research activities as the director of the Fertility and Endocrine Clinic at the Free Hospital for Women and Boston in Brookline, Massachusetts from 1926 to 1956; and later as the founder of the Rock Reproductive Study Center. The collection also contains records from Rock’s professional activities as a family planning advocate and administrator, surgeon, and faculty member of the Harvard Medical School. A limited amount of his personal correspondence is also included in this collection.

The bulk of the collection contains Rock’s research records from his tenure as director of the Fertility and Endocrine Clinic at the Free Hospital for Women, and includes research notebooks, correspondence, data, correspondence, memoranda, research files, and patient records, including files, laboratory microscope slides, and photographs produced from his clinical activities. The collection also includes Rock's collaborative writings, reproductive health research notes, and correspondence with colleagues Arthur Hertig, Gregory Pincus, Min-Chueh Chang, Celso-Ramon Garcia, Edris Rice-Wray, and Rock's laboratory assistant Miriam Menkin. Additional writings, lecture notes, film reels, and audio recordings produced from his reproductive health research address such topics as the development of the birth control pill, in vitro fertilization, sperm freezing for preservation, corpus luteum, and human embryo development. Rock's lecture notes from his classes taught at Harvard Medical School are found in Series IV. Rock's personal correspondence is housed in Series III and Series VII. Several photographs of Rock are also located in Series VII.

Biographical Note

John C. Rock (1890-1984) was the founder of the Rock Reproductive Study Center at the Free Hospital for Women in Brookline, Massachusetts, and Clinical Professor of Gynecology at Harvard Medical School. Rock collaborated with colleague Gregory Pincus and Pincus's assistant Min-Chueh Chang, during the 1950s in the clinical trials and development of oral contraceptives, commonly known as the birth control pill. Rock is also credited with colleague Arthur Hertig and laboratory assistant Miriam F. Menkin for completing the earliest human in vitro fertilization experiments in the United States in 1944. As a fertility specialist, gynecologist, and medical educator, Rock, a Roman Catholic, gained notoriety for advocating the usage of birth control despite his religious beliefs. His research areas included fertility, early stages of contraception, human embryo development, in vitro fertilization, the freezing and preservation of sperm cells, and clinical disorders of human reproductive physiology.

John Charles Rock was born on March 24, 1890 in Marlborough, Massachusetts. He received an S.B. from Harvard College in 1915, and his MD from Harvard Medical School in 1918. Rock began his residency in obstetrics at the Boston Lying-In Hospital in 1919. He held several academic appointments at Harvard Medical School between 1922 and his retirement from the Harvard Medical School faculty in 1956, culminating in his appointment as Clinical Professor of Gynecology. Rock taught clinical obstetrics for over 30 years at Harvard Medical School.

Rock was initially trained as a surgeon whose early medical career focused on infertility. As a medical educator at Harvard Medical School in Boston, Massachusetts, a state which at the time had legally banned the distribution of contraceptives, Rock covertly taught students the advantages of these methods. In 1931, Rock signed The Doctors’ Bill to Clarify the Law, a petition signed with other 15 physicians endorsing birth control and permitting doctors to prescribe, and chartered hospitals to dispense contraceptive devices.

From 1926 to 1956, Rock was the director of the Fertility and Endocrine Clinic at the Free Hospital for Women, one of the first centers of its kind in the United States. Rock created the Rhythm Clinic at the Free Hospital for Women in 1936 as a facility to educate women of the timing of their menstrual cycles to increase their chances of conception. Rock and Hertig collaborated, with Menkin’s assistance, to determine the time sequence of fertilization, ovum transport, and implantation. Their research, funded by the Carnegie Institute of Washington, led to Rock and Hertig's being the first researchers to attempt the fertilization of human ovum in vitro in 1944; and their recovery of human embryos from two to seventeen days after fertilization.

Upon his retirement from Harvard Medical School and the active staff of the Free Hospital for Women in 1956, Rock founded the independent Rock Reproductive Study Center, later known as the Rock Reproductive Clinic, Inc., in Brookline, Massachusetts. At this facility, Rock’s research focused on fertility and sterility and the development of oral contraceptives, commonly known as the birth control pill. In the early 1950s, Rock partnered with Gregory Pincus, and his assistant Min-Chueh Chang, to develop a progestin-based oral contraceptive that could halt ovulation in females. Their research was largely funded by Katherine Dexter McCormick, heiress to the McCormick reaper fortune, and was ardently supported by birth control pioneer Margaret Sanger. Pincus and Chang demonstrated the effectiveness of progestins as an ovulation inhibitor in their experiments in rabbits and rats in their research at the Worcester Foundation for Experimental Biology. Following their positive results, in 1954, Rock successfully tested oral progestins to prevent ovulation in a select group of 27 of his infertility patients. Rock instructed his patients to start taking the progesterone pills five days after the start of their menstrual periods. For the next three months, the women took the pills for twenty consecutive days, and then resumed taking the oral progesterone the fifth day after their next period. Within four months of taking the pill, four of the women were pregnant, indicating a fertility rebound, commonly known as the Rock Rebound, after taking the pill; the results also revealed oral progesterone could halt ovulation, thus preventing pregnancy.

With the success of the progestins in both studies, a controlled field trial of the newly-developed oral contraceptive was then completed in San Juan, Puerto Rico in 1956, with the assistance of colleague Celso-Ramon García and Edris Rice-Wray, Medical Director of the Puerto Rico Family Planning Association and Director of the United States Public Health Field Training Center. The Puerto Rico field trial was a success for Pincus and Rock, with 265 women participating in the trial by taking the pill for 20 days for six months. Subsequent pregnancies occurred in 85 percent of the women who stopped taking the pill in order to get pregnant. The Food and Drug Administration (FDA) approved the newly-developed progesterone pill as a treatment for menstrual disorders in 1957 on the basis of the Puerto Rico field trial results. After further trials, including a second trial in Puerto Rico, the FDA approved Enovid, developed by Searle Pharmaceuticals as the first birth control pill, for contraceptive use in 1960.

Rock garnered extensive publicity for his role in the development of the birth control pill. Much of the attention was centered on Rock's Catholic beliefs, and his willingness to support the pill despite his faith's opposition. In 1963, Rock published The Time Has Come: A Catholic Doctor’s Proposals to End the Battle Over Birth Control, a book which advocated for the widespread acceptance of the birth control pill as a legitimate contraceptive device, and was a direct challenge to the Catholic Church's traditional stand against contraceptives. After publishing his book, Rock lectured extensively in the United States, Europe, South America, and Asia, defending the pill as a means of natural contraception and warning audiences of the dangers of global overpopulation. The Catholic Church remained adamant in its opposition to the birth control pill, and Rock's research. In 1968, Pope Paul VI issued an encyclical, Humanae Vitae, renewing the Church's prohibition of artificial forms of birth control, including the pill.

Rock maintained his Reproductive Clinic through the late 1960s, affiliated with Harvard Medical School until 1967. He sold his practice in 1969 to Dr. John H. Derry of Newton, Massachusetts, who established the Derry-Rock Clinic in Roxbury, Massachusetts. Rock remained at the clinic performing research activities until 1971 when at age 80, he retired to Temple, New Hampshire.

John C. Rock died after a brief illness in 1984. He was 94 years old.

Series and Subseries in the Collection

  1. I. Free Hospital for Women Administrative Records, 1940-1972, undated
  2. ___A. Administrative Records, 1950-1972, undated
  3. ______1. Administrative Correspondence and Records, 1950-1972, undated
  4. ______2. Annual Reports, 1940-1968
  5. ___B. Rock Reproductive Study Center Correspondence and Personnel Records, 1932-1972
  6. ______1. Correspondence and Personnel Records, 1948-1972
  7. ______2. Administrative Records, 1932-1968
  8. II. Reproductive Research Records, 1925-1983, undated
  9. ___A. Reproductive Research Records and Correspondence, 1925-1983, undated
  10. ______1. Reproductive Research Records, 1936-1983, undated
  11. ______2. Patient Records, 1925-1972, undated
  12. _________a. Patient Ledgers, 1948-1970
  13. _________b. Reproductive Research Patient Files, 1925-1972, undated
  14. ____________(1) Patient Research Files, 1925-1972, undated
  15. ____________(2) F. Urine and Vaginal Smears, Eggs Treated with Sperm, Records, August 1944-, Records, 1945-1952, undated
  16. ____________(3) Gonadophysin Records, 1937-1943, undated
  17. ____________(4) Operated on, Some of these Gonads and Hyaluronidase, Records, 1938-1950, undated
  18. ______3. Research Images and Slides, 1935-1968, undated
  19. _________a. Research Images, 1935-1968, undated
  20. _________b. Microscope Slides, 1937-1950, undated
  21. ___B. Human Spermatozoa Research Records, 1938-1970, undated
  22. ___C. Research Correspondence, 1948-1972, undated
  23. ___D. Research and Reference Notecards, 1941-1967, undated
  24. III. Correspondence, 1932-1983
  25. IV. Outreach Activities Records, 1937-1972, undated
  26. ___A. Writings, 1937-1972, undated
  27. ______1. Reproductive Research Writings, 1937-1972, undated
  28. ______2. Tuboplasty Writings, 1950-1956, undated
  29. ___B. Lectures, Speeches, and Speaking Engagement Records, 1946-1972, undated
  30. ___C. Audio-visual Items, 1940, 1948, 1963-1967, undated
  31. ___D. Newsclippings, 1963-1965, 1968
  32. ___E. Subject Files, 1956-1969, undated
  33. V. Teaching Records, 1949-1972
  34. ___A. Harvard Medical School Teaching Records, 1949-1972
  35. ___B. Non-Harvard Medical School Teaching Records, 1951-1961
  36. VI. Professional Activities Records, 1945-1968, undated
  37. VII. Personal and Biographical Records, 1921-1985, undated


The John C. Rock Papers consist of seven series: Series I. Free Hospital for Women Administrative Records; Series II. Reproductive Research Records; Series III. Correspondence; Series IV. Outreach Activities Records; Series V. Professional Activities Records; Series VI. Teaching Records; and Series VII. Personal and Biographical Records. Media, including CD-ROMs and DVDs dubbed from Rock's film reels are available in box 33. Original film reels are located in box 35. Fragile original film reels are housed in box 36 in the Center for the History of Medicine's stacks. Oversized items are housed in boxes 25, 26, and 34. Additional oversized items are housed in row 1 of the Center for the History of Medicine's stacks. Boxes 29-31, and 36 are located in row 1, unit 6, shelves 5 and 6 of the Center for the History of Medicine's stacks. There are several photographs including candid photographs of Rock with colleagues and his family located in Series VII. Personal and Biographical Records.

Immediate Source of Acquisition

The John Rock papers were donated to the Harvard Medical Library in the Francis A. Countway Library of Medicine by Miriam Menkin.

Related Material in the Francis A. Countway Library of Medicine, Center for the History of Medicine

Consult Public Services for further information.

Related Records at Other Institutions

The Gregory Pincus Papers, 1920-1969 (bulk 1950-1967), can be found at the Library of Congress Manuscript Division, Washington, D.C.

The Planned Parenthood Federation of America Records, 1915-1974, can be found at Smith College, Sophia Smith Collection.

The Planned Parenthood Federation of America Records, 1921-1981, can be found at Smith College, Sophia Smith Collection.

Processing Information

Processed by Jennifer Pelose, 2007 February and Bryan Sutherland, 2015 March

Processing staff in the Center for the History of Medicine arranged, refoldered, reboxed, and created a finding aid for the John C. Rock Papers. Processing staff discarded duplicate records and records that did not meet the collection policy of the Center for the History of Medicine. Folder titles have been transcribed from Rock's original files.

Records in the series "Miriam Menkin Personal Records" (all of boxes 23 and 24, selected records from boxes 22, 25, and 34) have been removed and will be processed as part of a separate collection. Boxes 23 and 24 have not been replaced in the box numbering list.

Rock, John Charles, 1890- . Personal and Professional Papers, 1921-1985: Finding Aid.
Francis A. Countway Library of Medicine. Center for the History of Medicine.
Language of description

Repository Details

Part of the Center for the History of Medicine (Francis A. Countway Library of Medicine) Repository

The Center for the History of Medicine in the Francis A. Countway Library of Medicine is one of the world's leading resources for the study of the history of health and medicine. Our mission is to enable the history of medicine and public health to inform healthcare, the health sciences, and the societies in which they are embedded.

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