Improvement in early human embryo development using new formulation sequential stage-specific culture media.

OBJECTIVE: To determine whether altering selected components of sequential culture media can improve early development variables of human embryos. DESIGN: Prospective, randomized, sibling oocyte split trial. SETTING: Private ART center. PATIENT(S): Two hundred eight undergoing treatment with in vitro fertilization or microinjection. INTERVENTION(S): Oocytes from each patient were randomly allocated to fertilization and cleavage media of a control and a trial culture medium formulation. MAIN OUTCOME MEASURE(S): Rates of fertilization, cleavage, and uncontrolled division; average embryo morphology score; blastomeres per embryo; embryo score parameter (number of blastomeres x embryo morphology grade); and embryo utilization. The trial media resulted in a higher fertilization rate, higher cleavage rate, lower rate of uncontrolled division, higher number of blastomeres per embryo, higher average embryo morphology score, a higher embryo score parameter, and higher embryo utilization rate compared to the control media. All differences were statistically significant. CONCLUSION(S): Improved sequential stage-specific culture media can reduce the occurrence of severe human embryo fragmentation and improve developmental variables in early IVF- and ICSI-generated embryos.

Objective assessments of temperature maintenance using in vitro culture techniques.

PURPOSE: To assess the ability of various facets of embryo culture (microscope stage warmers, volumes of culture media, culture vessel lids, and type of culture incubator) to maintain a constant temperature in vitro. METHODS: Ability to maintain 37.0 degrees C in the microenvironment of gametes was recorded by digital thermocouple in the chosen facets of in vitro culture. RESULTS: Stage warmers are highly variable in their ability to maintain the set temperature (range 33.8 degrees C-37.0 degrees C after 60 s). Temperature loss in culture media is both volume and vessel dependent, and the direct heat transfer culture incubator (MINC) has superior temperature maintenance compared with a large volume air convection incubator (FORMA), where temperature regain from 35.0 degrees C to 37.0 degrees C took 5.5 min compared to >20 min. CONCLUSIONS: There are large measurable differences in the ability to maintain set temperature that depend on the stage warmer used, volume of media, use of vessel lids, and the type of incubator chosen for IVF culture.