[Pregnancy and delivery with transfer of vitrified blastocysts following trophectoderm biopsy]. / Terhesség és szülés trophectoderma-biopsziát követoen vitrifikált blasztociszták beültetésével.

Application of preimplantation genetic diagnosis makes it possible to transfer only embryos unaffected by a certain genetic disorder. The authors have applied the combination of trophectoderm biopsy and vitrification in order to detect a monogenic disorder. Previously diagnosed type 1 neurofibromatosis of the woman was the indication for genetic examination. In vitro fertilisation and embryo culture was performed using sequential culture mediums. Seven blastocysts could be sampled on the fifth day and were vitrified subsequently. Two blastocysts turned out to be genetically normal based on the result of genetic examination using polimerase chain reaction. A healthy boy was delivered following the transfer of warmed blastocysts and an uneventful singleton pregnancy.

Prediction of in-vitro developmental competence of early cleavage-stage mouse embryos with compact time-lapse equipment.

Single blastocyst transfer is regarded as an efficient way to achieve high pregnancy rates and to avoid multiple pregnancies. Risk of cancellation of transfer due to a lack of available embryos may be reduced by early prediction of blastocyst development. Time-lapse investigation of mouse embryos shows that the time of the first and second cleavage (to the 2- and 3-cell stages, respectively) has a strong predictive value for further development in vitro, while cleavage from the 3-cell to the 4-cell stage has no predictive value. In humans, embryo fragmentation during preimplantation development has been associated with lower pregnancy rates and a higher incidence of developmental abnormalities. Analysis of time-lapse records shows that most fragmentation is reversible in the mouse and is resorbed in an average of 9 h. Daily or bi-daily microscopic checks of embryo development, applied routinely in human IVF laboratories, would fail to detect 36 or 72% of these fragmentations, respectively. Fragmentation occurring in a defined time frame has a strong predictive value for in-vitro embryo development. The practical compact system used in the present trial, based on the 'one camera per patient' principle, has eliminated the usual disadvantages of time-lapse investigations and is applicable for the routine follow-up of in-vitro embryo development.

Effect of nickel (ni(2+)) on primary human ovarian granulosa cells in vitro.

Human ovarian granulosa cells obtained from women undergoing in vitro fertilization were exposed to 15.6, 31.25, 62.5, 125, 250, 500, 1000 muM Ni(2+) for 48 h. To determine the site of action of Ni(2+), the granulosa cells were stimulated to produce progesterone (P) by using maximally stimulating amounts of human chorionic gonadotropin (0.1 IU/ml hCG) or dibutyryl cyclic adenosine monophosphate (1 mM db-cAMP). The luteinizing hormone (LH) analog hCG was chosen because resultant P production requires an intact membrane receptor and db-cAMP was used to test for post LH receptor defects caused by Ni(2+). Progesterone content of the culture medium was determined by radioimmunoassay (RIA), and viability of the cells was measured by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) reduction test. Concentration-dependent depression in both hGC and db-cAMP stimulated P production was seen at 15.625 muM or higher concentration of Ni(2+), which is not cytotoxic on human ovarian granulosa cells. The viability of cells was unaffected up to 31.25 muM and decreased significantly at 62.5 muM. Our results show a dose-related depression in stimulated P production of granulosa cells at a dose that does not induce significant cytotoxic action. These data indicate that the effect of Ni(2+) on P production is not due to cytotoxicity, and the cellular site(s) of inhibitory action appears to be subsequent to the membrane receptor and production of cAMP.