[Autoradiographic study of the early stages of human female meiosis in organ culture].

Incorporation of H3-thymidin in developing germinative cells and the movement of the label in successive stages of preprophase and prophase of meiosis were studied in the organic culture of the ovaries of 7-12 and 23 week human embryos by the method of autoradiography. H3-thymidin was incorporated by oognia and oocytes of the last stages of preleptotene with a thin uneven network of chromatin in the nucleus and by oocytes of the stage of leptotene and, rarely, zygotene. In oocytes with prochromosomes the label appeared within 12 hours. The cells labeled in the premeiotic DNA synthesis were changed into the zygotene stage within 4 days, into the pachytene stage- within 14 days. The development took 7-14 days from the last premitosis S-period to zygotene. Oogoniums divided two times for 7 days. Gz-period of oognia -1/2 of mitosis lasts an average of 10 hours. The S-period of oogonia lasts for about 9 hours.