A new method for preparation of culture media for IVF-ET and GIFT was developed which eliminated the requirement for volumetrics and glassware. Water weight was used instead of volumetrics for preparation of media. Media prepared by the volumetric and water weight methods were compared for (i) preparation time, (ii) pH, (iii) osmolarity and (iv) the percentage of two-cell murine embryos developing to blastocysts. The time required for preparation of media was significantly less for the water weight method. Following equilibration with 5% CO2, no differences were observed between the two methods for pH, osmolarity or development of embryos to the blastocyst stage. Time for media preparation and osmolarity was less variable among preparation days for the water weight method. These results suggest that media can be prepared more efficiently and precisely with the water weight method than with the standard volumetric method used by most IVF laboratories. The former method eliminates considerable technician time which must be devoted to proper cleaning/sterilization of volumetrics and the possibility of media contamination by residual substances remaining on volumetrics following improper cleaning.