Regnier de Graaf

Regnier de Graaf (July 30, 1641 – August 17, 1673) was a Dutch physician and anatomist who made key discoveries in reproductive biology. His first name is often spelled Reinier or Reynier.

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Biography

De Graaf was born in Schoonhoven. After studying medicine in Utrecht and Leiden, where he submitted his doctoral thesis on the pancreas, he went to France where he obtained his medical degree from the University of Angers. While in Paris, he also turned to the study of the male genitalia, which led to a publication in 1668. Back in the Netherlands in 1667, De Graaf established himself in Delft. Since he was a Catholic in a mainly Protestant country, he was unable to follow a university career. After the early death of a son, De Graaf died in 1673 at age 32 and was buried in the Oude Kerk in Delft. The reason for his death is unknown, he was, however, affected by his controversy with Swammerdam (v.i.) and the death of his son. Recent speculation that he may have committed suicide is entirely unfounded. A few months before his death De Graaf recommended, as a member of the Royal Society in London, that attention be paid to Antonie van Leeuwenhoek and his work on the improvement of the microscope.

Legacy

De Graaf is famous for having realised the reproductive function of the ovarian follicle. From the observation of pregnancy in rabbits, he concluded that the follicle contained the oocyte, although he never observed it. The mature stage of the ovarian follicle is called the Graafian follicle in his honour, although others, including Fallopius, had noticed the follicles previously (but failed to recognize its reproductive significance). The term Graafian follicle followed the introduction of the term ova Graafiana by Albrecht von Haller who still assumed that the follicle was the oocyte itself. The discovery of the human egg was eventually made by Karl Ernst von Baer in 1827. De Graaf's contemporary Jan Swammerdam confronted him after his publication of DeMulierum Organis Generatione Inservientibu and accused him of taking credit of discoveries he and Johannes van Horne had made earlier regarding the importance of the ovary and its eggs. De Graaf issued a rebuttal but was affected by the accusation.^[1]

De Graaf may have been the first to understand the reproductive function of the Fallopian tube, described the hydrosalpinx, and linked the development of hydrosalpinx with female infertility.^[2] De Graaf described as a first female ejaculation and referred to a erogene zone in the vagina that he himself linked with the male prostate; later this zone was rediscovered by the German gynecologist Ernst Gräfenberg as the g-spot. Further, he described the anatomy of the testicles and collected secretions of the gall bladder and the pancreas.

De Graaf's discoveries were made without the benefit of a microscope.

Gallery

Publications

• De Graaf, R (1668) De Virorum Organis Generationi Inservientibus, de Clysteribus et de Usu Siphonis in Anatomia
• De Graaf, R (1672) De Mulierum Organis Generationi Inservientibus
• De Graaf, R (1686) Alle de Wercken. Leyden, The Netherlands.

References

• Houtzager HL. Reinier de Graaf 1641-1673 (Dutch). Rotterdam: Erasmus publishing, 1991. ISBN 90-5235-021-3.