Provided is a subcutaneous injection preparation that can induce superovulation in a cow by only one administration and, therefore is useful for producing good calves, said subcutaneous injection preparation containing an aluminum hydroxide gel and an efficient amount of a gonadotropic hormone and being characterized in that the concentration of aluminum hydroxide, in terms of aluminum, is 0.2 mg/mL or higher and lower than 1.0 mg/mL. Also provided is a method for producing good calves, said method comprising steps for subcutaneously injecting the aforesaid injection preparation into a cow to thereby induce superovulation, inducing estrus in the cow, conducting artificial insemination, and then collecting fertilized eggs.