Europ. J. Obstet. Gynec. reprod. Biol., 13 (1982) 109-110 Elsevier Biomedical Press

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CLASSIC ILLUSTRATION

G-

2-

age (months p.c.)

FIG-E 1. Calculated numbers of germ cells per pair of ovaries. Total (-), normal (----) and atretic (------) germ cells

Figure taken from: Baker, T.G. (1963): A quantitative and cytological study of germ cells in human ovaries. Proc. R. Sot. Biol., 158, 417-433. Reproduced with permission.

T.G. Baker published this work from the Department of Anatomy, Uni- versity of Birmingham. Forty-six fetal, five neonatal and fifteen postnatal (prepubertal) specimens were examined. It was a real multi-center study because ‘of the total of sixty-six ovaries used in the present study, twenty- five were generously supplied by Professor G.P. Gaillard of the University of

0028-2243/82/000~0000/$02.75 @ 1982 Elsevier Biomedical Press

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Leiden, and five by courtesy of Dr. Egon Diczfalusy of the Karolinska Sjuk- huset, Stockholm’.

The ages of the fetuses were assessed both from the crown-rump length, using the data of Streeter and from the date of the last menstrual period.

Material from spontaneous abortions were only used when no marked autolytic changes were present.

The material was fixed in Bouin’s aqueous fluid and serially sectioned at 5-10 pm.

Squash preparations were made, the ovarian volume was calculated planimetrically, cell and nuclear volumes were measured and populations of oocytes calculated.

The total population of germ cells rose steadily from 600,000 at 2 mth postconception, reaching a peak of 6,800,OOO at 5 mth. By the time of birth, the number declined to 2,000,OOO of which some 50% were atretic. Of the l,OOO,OOO normal oocytes in the newborn infant, only some 300,000 survive to the age of 7 yr.

This illustration will be frequently used in a slide-presentation of lecturers in the field of reproduction. It still triggers the basic genetic and hormonal environment of the fetus responsible for this ‘survival of the fittest?‘.

Baker has to be congratulated with this work for it enables us to trigger more people to study the ‘miracles’ of reproduction.

T.K.A.B.ESKES Nijmegen