Talk:Paper - On a human blastula recovered from the uterine cavity 4 days after ovulation

From Embryology

This 1946 paper presented by Hertig and Rock at the 1946 Meeting of the American Association of Anatomists.

47. On a human blastula recovered from the uterine cavity 4 days after ovulation (Carnegie, no. 8190).

Arthur T. HERTIG and John ROCK,

Departments of Obstetrics, Pathology and Gynecology, Harvard Medical School and the Department of Embryology, Carnegie Institution of Washington,

The specimen was recovered from a uterus removed surgically on the twenty-first day of a menstrual cycle previously ranging from 25 to 32 days duration. Probable fertile coitus occurred 4% days previously. Endometrium morphologically was characteristic of the eighteenth day, ovulation having occurred 4 days previously. The stigma of the recent corpus luteum was unhealed.

The free-lying blastula was obtained in Locke ’s solution removed by pipette from the cavity of a submerged uterus opened completely at one side and partially across the fundus. The specimen was discovered with a binocular dissecting microscope using 10 diameters of magnification. Fresh, the specimen measured 190 X 150 micra but after fixation in Bouin’s fluid, begun 1 hour after removal of the uterus, it measured 175 X 124 micra. It was surrounded by a sticky, thick, transparent, refractile vitelline membrane which shrank during fixation.

Following dehydration and embedding in celloidin-parafiine, 15 perfect serial sections of 6 micra each were obtained by Dr. Chester Heuser. Nine blastomercs of varying size and shape are present: 5 containing 1 nucleus each, 3 with 2 nuclei each and 1 with 3 nuclei. Three of the single-nucleated blastomeres are in varying stages of mitosis. A segmentation cavity is just beginning to form.

Because of the presence of multinucleated blastomeres the specimen is probably not normal, although no other human specimen is available for comparison.