Pressure changes during embryo transfer

Pressure induced nucleus DNA fragmentation

“…In the present study, much lower pressure changes,~76 mmHg, were able to cause pressure DNA shearing (PDS) inside the nucleus of a living cells. According to our recent studies, the pressure fluctuations of comparable magnitude could also appear during embryo transfer procedure (ET) and cause both morphological and apoptotic changes in the embryos exposed to ET [12,18]. Taking under consideration the entire process of extracorporeal fertilization, the significant pressure fluctuations could also emerge during oocyte pickup, oocyte decoronization and embryo pipetting.…”

“…For example, in the case of ET the pressure build up in the transferred liquid is proportional to the speed of ejection of the transferred load. For that reason, it is reasonable to suggest transferring the embryos at the lowest possible ejection speed [12,18].…”

Fluid dynamics during embryo transfer

“…Overall, the pressure generated in the working chamber of the insulin syringe is passed into the catheter where it causes ejection of the transferred load. The disproportion between the diameters of the syringe plunger and the catheter lumen creates favorable conditions for the fast fluid flow inside the catheter, reaching 12 m/sec on average (5).…”

“…The tip narrowing was assumed to be 20% of the diameter of the inner compartment. The uterus model was built with 2 rigid walls, set 2 mm apart, according to the experimental approach presented in the previous article (5). Embryo culture medium properties were assumed to be those of liquid water (density r ¼ 998.2 kg/m 3 ; dynamic viscosity m ¼ 0.001003 kg/[m$sec]).…”

“…The study conducted previously by our team demonstrated that ET performed with the standard insulin syringe-catheter complex was able to affect mouse blastocyst viability (4). The abrupt alterations in the embryo's environment during ET were the most probable cause for the observed morphological and apoptotic changes in the mouse blastocysts (4,5).…”