Superovulation is a technique used to get female mice to release more eggs than normal. It is a critical step in collection zygotes for mouse line re-derivation, IVF, and collection morulae for mouse embryo cryopreservation. Zygotes are collected at 0.5dpc, morulae are collected at 2.5dpc.

 Hormone stock reconstitution:

• PMSG (sigma G4877-1000IU) is reconstituted from a lyophilized powder at an activity of 1000 IU per vial by adding 3.6 ml of sterile PBS.  100ul  microliters are then aliquoted into 1.5 ml tubes. Tubes are labeled and stored in -20 °C freezer.
• hCG (sigma C1063-10VL)is reconstituted from a lyophilized powder at an activity of 10,000 IU per vial by adding 1.8 ml of sterile PBS. 100 microliters are then aliquoted into 1.5 ml tubes. Tubes are labeled and placed in -20 °C freezer. 

Animals:

• Female age: ~4 weeks of age at time of PMSG administration. 
• Male age: 8-24 weeks stud male, each male is set up only once per week. 

Hormone concentrations and injections:

• Each PMSG stock tube is diluted with 1ml sterile PBS. Each female is then injected with 0.1 ml. (1 tube each should provide enough hormone for 10 females). Final dose 5 IU/female.
• Each HCG tube is also diluted with 1ml of sterile PBS. Each female is then injected with 0.1 ml. (1 tube each should provide enough hormone for 10 females). Final dose 5 IU/female.
• All injections are delivered intraperitoneally.

Hormone time schedule:

• PMSG on Day 1 at 1:00 p.m., HCG on Day 3 at 12:00 p.m., Set-up female with male on Day 3 after hCG injection.