Pregnancy after vitrification of pronuclear stage oocytes biopsied for polar body aneuploidy screening

Abstract

This paper reports the case of a patient undergoing IVF and polar body analysis for aneuploidy screening because of advanced maternal age. A total of nine fertilized oocytes were obtained from the patient's third treatment cycle. Three supernumerary pronuclear stage oocytes were identified as suitable after aneuploidy screening for five chromosomes and vitrified. Because the fresh cycle did not result in a pregnancy, vitrified pronuclear stage oocytes were warmed for transfer in an artificial cycle. All three zygotes survived warming and were transferred to the patient's uterus 2 days later as 4-, 5- and 6-cell stage embryos. After 2 weeks, a positive pregnancy test indicated successful implantation. The gestation is developing normally and is presently (end of September 2007) in the 22nd week.

High survival rate of metaphase II human oocytes after first polar body biopsy and vitrification: determining the effect of previtrification conditions

“…Five experimental groups were tested: [1] control (no treatment) at 37 C; [2] zona slitting and vitrification at 37 C; [3] zona slitting, first polar body biopsy, and vitrification at 37 C; [4] zona slitting and vitrification at 22 C; and [5] zona slitting, first polar body biopsy, and vitrification at 22 C. A total of four replications were performed for each group. All MII bovine oocytes were vitrified in 2.6 mol/L DMSO þ 3.3 mol/L EG (ED20).…”

“…In addition, preimplantation genetic diagnosis using polar body biopsy has become a valuable component of assisted reproductive technologies for preventing autosomal dominant disorders such as X-linked dominant diseases in women, as well as recessive disorders (1)(2)(3)(4)(5). Recently, there has been an increasing effort to cryobank human oocytes similar to sperm cryobanking, which has helped thousands of infertile couples.…”

“…Because new vitrification technology has provided a sea change in outcome results (5), to date, oocyte cryopreservation still is far less successful for nearly all mammalian species, with the exception of the mouse, in comparison with sperm and the preimplantation embryo (6). Research conducted over the past decades has demonstrated clearly that there are fundamental reasons for the susceptibility of mammalian oocytes to cryopreservation-induced injury, which prevents normal fertilization, as well as developmental progression to preimplantation stage embryos, including their sensitivity to cryoprotective agents and suboptimal conditions during the cryopreservation procedure (7).…”

Blastocyst transfer after aseptic vitrification of zygotes: an approach to overcome an impaired uterine environment

“…Surprisingly, this method has not reached the same level of popularity when it comes to the cryopreservation of human 2PN embryos. Only a handful of cases and findings have been published (Isachenko et al, 2004(Isachenko et al, , 2005Liebermann and Tucker, 2002;Naether et al, 2008;Park et al, 2000;Selman and El-Danasouri, 2002) and the number of manuscripts describing the clinical application of 2PN vitrification remains extremely limited (Al-Hasani et al, 2007;Kuwayama et al, 2005), even though cryopreservation is justified for a wide range of different reasons as previously stated.…”

Polkörperdiagnostik

“…Theoretisch könnten die zeitlichen Probleme durch das Einfrieren der Eizellen nach der Biopsie und das zeitgerechte Auftauen der intakten Eizellen nach CGH in einem Folgezyklus überwunden werden. Für dieses Vorgehen sind jedoch die Erfolgsraten nach dem Einfrieren und Auftauen von zuvor biopsierten Eizellen derzeit noch zu gering [39] .…”