"Unwanted mating" refers to a situation where two animals or organisms engage in reproduction without one or both parties desiring or intending to do so. Full definition
They're being used globally to prevent unwanted mating. (littledogtips.com)
An unsterilized pet is less desirable (due to unwanted mating behaviors like roaming, mounting, howling and caterwauling) AND can produce unwanted litters, compounding the problem of too many homeless pets. (ocgainesville.org)
This way, we prevent the unwanted mating of young immature bitches, and at same time we prevent the possible accidental mating of close relatives (ie. (breedingbusiness.com)