Altered cleavage patterns in human tripronuclear embryos and their association to fertilization method: a time-lapse study.

PURPOSE: To analyze the cleavage patterns in dipronuclear (2PN) and tripronuclear (3PN) embryos in relation to fertilization method. METHOD: Time-lapse analysis. RESULTS: Compared to 2PN, more 3PN IVF embryos displayed early cleavage into 3 cells (p < 0.001), displayed longer duration of the 3-cell stage (p < 0.001), and arrested development from the compaction stage and onwards (p < 0.001). For the IVF embryos, the 2nd and 3rd cleavage cycles were completed within the expected time frame. However, timing of the cell divisions within the cleavage cycles differed between the two groups. In contrast, the completion of the 1st, 2nd, and 3rd cleavage cycle was delayed, but with a similar division pattern for 3PN ICSI compared with the 2PN ICSI embryos. 3PN, more often than 2PN ICSI embryos, displayed early cleavage into 3 cells (p = 0.03) and arrested development from the compaction stage and onwards (p = 0.001). More 3PN IVF than ICSI embryos displayed early cleavage into 3 cells (p < 0.001). CONCLUSIONS: This study reports differences in cleavage patterns between 2PN and 3PN embryos and for the first time demonstrates differences in the cleavage pattern between 3PN IVF and ICSI embryos.

Cell-free DNA in pregnancy with choriocarcinoma and coexistent live fetus: A case report.

BACKGROUND: This case report describes the use of analysis of cell-free DNA in the blood of a patient with a pregnancy with one live fetus and a choriocarcinoma diagnosed at 22 weeks of gestation. RESULTS: The result of the analysis of 16 microsatellite loci on 14 chromosomes in the cell-free DNA in plasma was consistent with the result of the analysis of a tumor biopsy indicating biparental diploid origin of the genome. The DNA markers were discordant with the markers of the placenta indicating two separate conceptions. CONCLUSION: Our results indicate that analysis of cell-free DNA in plasma allows determination of the origin of a choriocarcinoma without tissue biopsy, even in the presence of a co-existent pregnancy.

The parental origin correlates with the karyotype of human embryos developing from tripronuclear zygotes.

OBJECTIVE: It has previously been suggested that embryos developing from intracytoplasmic sperm-injected (ICSI) zygotes with three pronuclei (3PN) are endowed with a mechanism for self-correction of triploidy to diploidy. 3PN are also observed in zygotes after conventional in vitro fertilization (IVF). The parental origin, however, differs between the two fertilization methods. Whereas the vast majority of 3PN IVF zygotes are of dispermic origin and thus more likely to have two centrioles, the 3PN ICSI zygotes are digynic in origin and therefore, more likely to have one centriole. In the present study, we examine whether the parental origin of 3PN embryos correlates with the karyotype. METHODS: The karyotype of each nucleus was estimated using four sequential fluorescence in situ hybridizations-each with two probes-resulting in quantitative information of 8 different chromosomes. The karyotypes were then compared and correlated to the parental origin. RESULTS: 3PN ICSI embryos displayed a significantly larger and more coordinated reduction from the assumed initial 3 sets of chromosomes than 3PN IVF embryos. CONCLUSION: The differences in the parental origin-and hence the number of centrioles-between the 3PN IVF and the 3PN ICSI zygotes are likely to be the cause of the differences in karyotypes.