Markus Montag

The influence of temperature during incubation on the degree of sperm nuclear vacuolisation was assessed by two different experiments. In a first experiment, motile spermatozoa from 24 patients were prepared by the swim‐up technique and incubated either at room temperature or at 37 °C for up to 4 h. The presence of sperm nuclear vacuoles was determined by contrast‐enhanced high magnification microscopy. No statistically significant difference was found in the degree of sperm nuclear vacuoles in both groups (RT: 45.6 ± 17.6%; 37 °C: 48.4 ± 17.0%) following 4 h of incubation. In a second experiment, spermatozoa from six patients were either prepared by swim‐up or washed and incubated at 37 °C. After 4 h of incubation, a significant increase in sperm nuclear vacuolisation was found in washed sperm (from 51.5 ± 15.4% to 68.6 ± 9.0%; P < 0.05) but not in swim‐up sperm (from 51.5 ± 15.4% to 48.2 ± 17.1%; n.s.). Our data show that the mode of sperm preparation does influence sperm nuclear vacuolisation at 37 °C (Experiment II). However, sperm nuclear vacuolisation is unaffected by temperature in motile sperm after preparation and isolation by swim‐up.

Background: Cryopreservation of isolated follicles may be a potential option to restore fertility in young women with cancer, because it can prevent the risks of cancer transmission. Several freezing protocols are available, including slow-rate freezing, open-pulled straws vitrification (OPS) and solid-surface vitrification (SSV, a new freezing technique). The purpose of our study was to investigate the effects of these freezing procedures on viability, ultrastructure and developmental capacity of isolated rat follicles. Methods: Isolated follicles from female Sprague-Dawley rats were randomly assigned to SSV, OPS and slow-rate freezing groups for cryopreservation. Follicle viability assessment and ultrastructural examination were performed after thawing. In order to study the developmental capacity of thawed follicles, we performed in vitro culture with a three-dimensional (3D) system by alginate hydrogels. Results: Our results showed that the totally viable rate of follicles vitrified by SSV (64.76%) was slightly higher than that of the OPS group (62.38%) and significantly higher than that of the slow-rate freezing group (52.65%; P < 0.05). The ultrastructural examination revealed that morphological alterations were relatively low in the SSV group compared to the OPS and slow-rate freezing groups. After in vitro culture within a 3D system using alginate hydrogels, we found the highest increase (28.90 ± 2.21 μm) in follicle diameter in follicles from the SSV group. The estradiol level in the SSV group was significantly higher than those in the OPS and slow-rate freezing groups at the end of a 72-hr culture period (P < 0.05). Conclusions: Our results suggest that the SSV method is an appropriate and convenient method for cryopreservation of isolated rat follicles compared with the conventional slow-rate freezing method and the OPS method.

Polkörperdiagnostik (PKD) ist eine Methode zur indirekten genetischen Analyse von Eizellen. Polkörper sind Nebenprodukte des meiotischen Zellzykluses, die für die weitere embryonale Entwicklung keine Bedeutung haben. Die Biopsie der Polkörper kann durch mechanisches Zonadrilling oder durch laserassistierte Zonaeröffnung in kürzester Zeit durchgeführt werden. Der väterliche Anteil an der genetischen Konstitution des entstehenden Embryos kann mit der PKD nicht diagnostiziert werden. Der überwiegende Einsatz der PKD erfolgt zum Nachweis von mütterlichen Aneuploidien und Translokationen in Eizellen. Für diese Indikationen ist die PKD eine Alternative zur Entnahme von Blastomeren, da die Integrität des Embryos durch die PKD nicht gestört wird. Neue Entwicklungen im Bereich der molekulargenetischen Diagnostik werden auch die PKD beeinflussen und möglicherweise in naher Zukunft eine umfassendere Diagnose ermöglichen.